Implement Algorithm X for solving and generating sudokus
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@ -15,20 +15,11 @@ export const typeDefs = gql`
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"The height of each region."
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regionHeight: Int!
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"The total number of cells in the board."
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cells: Int!
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"The 'raw' board, an array of cells in region-first order."
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raw: [Cell!]!
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"The number of cells in the board."
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size: Int!
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"The rows of the board, from top to bottom."
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rows: [[Cell!]!]!
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"The columns of the board, from left to right."
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columns: [[Cell!]!]!
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"The regions of the board, book-ordered."
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regions: [[Cell!]!]!
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cells: [[Cell!]!]!
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}
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type Query {
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195
src/sudoku/dlx.ts
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195
src/sudoku/dlx.ts
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@ -0,0 +1,195 @@
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export class DNode {
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up: DNode;
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down: DNode;
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left: DNode;
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right: DNode;
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column: CNode;
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meta: any;
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constructor(column: CNode) {
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this.up = this.down = this.left = this.right = this;
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this.column = column;
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}
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}
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export class CNode extends DNode {
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left: CNode;
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right: CNode;
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size: number;
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name: string | undefined;
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constructor(name = undefined) {
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super(null!);
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this.column = this;
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this.size = 0;
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this.name = name;
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this.left = this.right = this;
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}
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}
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type SolutionCallback = (output: DNode[]) => boolean;
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type ColumnSelector = (header: CNode) => CNode;
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function selectColumnSizeHeuristic(header: CNode): CNode {
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let minSize = Infinity;
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let minColumn: CNode | undefined;
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let curColumn = header;
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while ((curColumn = curColumn.right) !== header) {
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if (curColumn.column.size < minSize) {
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minSize = curColumn.column.size;
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minColumn = curColumn;
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}
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}
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if (!minColumn) {
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throw new Error("minColumn is undefined, this shouldn't be possible.");
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}
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return minColumn;
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}
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export function linkNodesLR(nodes: DNode[]) {
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// given an array of nodes, link them together left-to-right circularly
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let last = nodes[0];
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for (let j = 1; j < nodes.length; j++) {
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const node = nodes[j];
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last.right = node;
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node.left = last;
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last = node;
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}
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nodes[0].left = last;
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last.right = nodes[0];
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return nodes;
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}
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export function addNodeToColumn(column: CNode, meta: any) {
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column.size++;
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let node = new DNode(column);
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node.down = column; // new last node, points down to column
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node.up = column.up; // new last node points up to previous last node
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// previous last node points down and column points up to new node,
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// repairing the circle
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column.up.down = column.up = node;
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node.meta = meta;
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return node;
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}
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export function maskRow(node: DNode) {
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let row = node;
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do {
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row.column.size--;
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row.down.up = row.up;
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row.up.down = row.down;
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} while ((row = row.right) !== node);
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}
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export function unmaskRow(node: DNode) {
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let row = node;
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do {
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row.column.size++;
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row.down.up = row.up.down = row;
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} while ((row = row.right) !== node);
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}
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export class DLX {
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header: CNode;
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updates: number = 0;
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callback: SolutionCallback;
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columnSelector: ColumnSelector;
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constructor(
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header: CNode,
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callback: SolutionCallback = () => false,
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columnSelector: ColumnSelector = selectColumnSizeHeuristic
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) {
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this.header = header;
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this.callback = callback;
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this.columnSelector = columnSelector;
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}
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cover(c: CNode) {
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// remove c from column header list
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c.right.left = c.left;
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c.left.right = c.right;
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this.updates++;
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let row = c as DNode;
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while ((row = row.down) !== c) {
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// traverse DOWN the rows this column contained
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let col = row;
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while ((col = col.right) !== row) {
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// traverse the columns of this row (to the RIGHT)
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// remove this node from its column, and shrink its column's size
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this.updates++;
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col.up.down = col.down;
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col.down.up = col.up;
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col.column.size--;
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}
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}
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}
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uncover(c: CNode) {
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let row = c as DNode;
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while ((row = row.up) !== c) {
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// traverse UP the rows this column contained
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let col = row;
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while ((col = col.left) !== row) {
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// traverse the columns of this row (to the LEFT)
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// do the inverse of cover()
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this.updates++;
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col.up.down = col.down.up = col;
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col.column.size++;
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}
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}
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// insert c back into column header list
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this.updates++;
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c.left.right = c.right.left = c;
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}
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solution: DNode[] = [];
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_search(k: number): boolean {
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if (this.header.right === this.header) {
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return this.callback(this.solution);
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}
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const column = this.columnSelector(this.header);
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this.cover(column);
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let complete = false;
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let row = column as DNode;
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while ((row = row.down) !== column) {
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// add this row to the partial solution
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this.solution[k] = row;
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// cover the columns of every other node on this row
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let curCol = row;
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while ((curCol = curCol.right) !== row) {
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this.cover(curCol.column);
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}
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complete = this._search(k + 1);
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curCol = row;
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while ((curCol = curCol.left) !== row) {
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this.uncover(curCol.column);
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}
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if (complete) break;
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}
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this.uncover(column);
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return complete;
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}
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search() {
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this.updates = 0;
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this._search(0);
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}
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}
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@ -1,15 +1,9 @@
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import { SudokuMath } from "./math";
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import { StaticPool, isTimeoutError } from "node-worker-threads-pool";
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import WORKERS from "physical-cpu-count";
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const TIMEOUT = 5000;
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const TIMEOUT = 20000;
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export type Cell = { value: number | null };
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export type CellArray = Cell[];
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export type Row = CellArray;
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export type Column = CellArray;
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export type Region = CellArray;
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export type Puzzle = CellArray;
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export type GenerateArguments = {
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regionWidth: number;
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@ -20,21 +14,16 @@ export type GenerateArguments = {
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export type Sudoku = {
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regionWidth: number;
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regionHeight: number;
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cells: number;
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raw: Puzzle;
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rows: () => Row[];
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columns: () => Column[];
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regions: () => Region[];
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size: number;
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cells: Cell[][];
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};
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const pool = new StaticPool<GenerateArguments, [any, Puzzle]>({
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const pool = new StaticPool<GenerateArguments, Cell[][]>({
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size: WORKERS,
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task: "./src/sudoku/worker.js",
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});
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const _math = new SudokuMath(0, 0);
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let activeWorkers = 0;
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export async function generate(
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regionWidth: number,
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regionHeight: number,
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@ -46,7 +35,7 @@ export async function generate(
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try {
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activeWorkers++;
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const [math, puzzle] = await pool.exec(
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const puzzle = await pool.exec(
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{
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regionWidth,
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regionHeight,
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@ -55,16 +44,11 @@ export async function generate(
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TIMEOUT
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);
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Object.assign(_math, math);
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return {
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regionWidth,
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regionHeight,
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cells: math.boardCells,
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raw: puzzle,
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rows: () => _math.regionsToRows(puzzle, true),
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columns: () => _math.regionsToCols(puzzle, true),
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regions: () => _math.chunkRegions(puzzle),
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size: (regionWidth * regionHeight) ** 2,
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cells: puzzle,
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};
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} catch (err) {
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if (isTimeoutError(err)) {
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@ -1,326 +1,278 @@
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import { Cell, Row, Column, Region, Puzzle } from "./index";
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import {
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clone,
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range,
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shuffle,
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chunkify,
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mapArray,
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addCellValuesToSet,
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} from "./util";
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DLX,
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DNode,
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CNode,
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linkNodesLR,
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addNodeToColumn,
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maskRow,
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unmaskRow,
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} from "./dlx";
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import { shuffle, range } from "./util";
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import { Cell } from "./index";
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function getTakenValues(region: Region, row: Row, col: Column) {
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const filter = new Set<number>();
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addCellValuesToSet(filter, region);
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addCellValuesToSet(filter, row);
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addCellValuesToSet(filter, col);
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return filter;
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}
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type NodeMeta = {
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row: number;
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col: number;
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region: number;
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value: number;
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};
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type BoardInfo = [number, number, number, number, number];
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export class SudokuMath {
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regionWidth: number;
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regionHeight: number;
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boardWidth: number;
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boardHeight: number;
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width: number;
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height: number;
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boardCells: number;
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regionCells: number;
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legalValues: number[];
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_regionsFromIndex: number[];
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_rowsFromIndex: number[];
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_colsFromIndex: number[];
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_rowIndexToRegionIndex: number[];
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_colIndexToRegionIndex: number[];
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_regionIndexToRowIndex: number[];
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_regionIndexToColIndex: number[];
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values: number;
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values2: number;
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indexes: number[];
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candidates: BoardInfo[];
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constructor(regionWidth: number, regionHeight: number) {
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this.regionWidth = regionWidth;
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this.regionHeight = regionHeight;
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this.boardWidth = regionHeight;
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this.boardHeight = regionWidth;
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this.width = regionWidth * this.boardWidth;
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this.height = regionHeight * this.boardHeight;
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this.boardCells = this.width * this.height;
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this.regionCells = regionWidth * regionHeight;
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this.legalValues = range(1, this.regionCells);
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this._regionsFromIndex = Array(this.boardCells);
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this._rowsFromIndex = Array(this.boardCells);
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this._colsFromIndex = Array(this.boardCells);
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this._rowIndexToRegionIndex = Array(this.boardCells);
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this._colIndexToRegionIndex = Array(this.boardCells);
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this._regionIndexToRowIndex = Array(this.boardCells);
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this._regionIndexToColIndex = Array(this.boardCells);
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this.values = regionWidth * regionHeight;
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this.values2 = this.values * this.values;
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for (let i = 0; i < this.boardCells; i++) {
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this._regionsFromIndex[i] = this._regionFromRegionIndex(i);
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this.indexes = Array(this.values2)
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.fill(null)
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.map((_, i) => i);
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const [row, col] = this._rowColFromRegionIndex(i);
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this._rowsFromIndex[i] = row;
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this._colsFromIndex[i] = col;
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const rowIndex = row * this.width + col;
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const colIndex = col * this.height + row;
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this._rowIndexToRegionIndex[rowIndex] = i;
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this._colIndexToRegionIndex[i] = rowIndex;
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this._regionIndexToRowIndex[i] = rowIndex;
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this._regionIndexToColIndex[colIndex] = i;
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}
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this.candidates = Array.from(Array(this.values ** 3), (_, i) =>
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this.getRowColRegionValFromCandidate(i)
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);
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}
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_regionFromRegionIndex(i: number) {
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return Math.trunc(i / this.regionCells);
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}
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regionFromRegionIndex(i: number) {
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return this._regionsFromIndex[i];
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}
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_rowColFromRegionIndex(i: number) {
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const region = this.regionFromRegionIndex(i);
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const cell = i % this.regionCells;
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const regionRow = Math.trunc(region / this.boardWidth);
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const regionCol = region % this.boardWidth;
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const cellRow = Math.trunc(cell / this.regionWidth);
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const cellCol = cell % this.regionWidth;
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getConstraintIDs(val: number, row: number, col: number, region: number) {
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return [
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regionRow * this.regionHeight + cellRow,
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regionCol * this.regionWidth + cellCol,
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// each cell has a value
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row * this.values + col,
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// each row has one of each value
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this.values2 + row * this.values + val,
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// each col has one of each value
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this.values2 * 2 + col * this.values + val,
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// each region has one of each value
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this.values2 * 3 + region * this.values + val,
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];
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}
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rowColFromRegionIndex(i: number) {
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return [this._rowsFromIndex[i], this._colsFromIndex[i]];
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getRowColRegionValFromCandidate(candidate: number): BoardInfo {
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const boardIndex = Math.floor(candidate / this.values);
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const row = Math.floor(boardIndex / this.values);
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const col = boardIndex % this.values;
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const region =
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Math.floor(row / this.regionHeight) * this.regionHeight +
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Math.floor(col / this.regionWidth);
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const val = candidate % this.values;
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return [candidate, row, col, region, val];
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}
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regionIndexToRowIndex(i: number) {
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return this._regionIndexToRowIndex[i];
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}
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rowIndexToRegionIndex(i: number) {
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return this._rowIndexToRegionIndex[i];
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}
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regionIndexToColIndex(i: number) {
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return this._regionIndexToColIndex[i];
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}
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colIndexToRegionIndex(i: number) {
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return this._colIndexToRegionIndex[i];
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}
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chunkRegions(cells: Cell[]) {
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return chunkify(cells, this.regionCells);
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}
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regionsToRows(cells: Cell[], split = false) {
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const rows = mapArray(cells, this._regionIndexToRowIndex);
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return split ? chunkify(rows, this.width) : rows;
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}
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regionsToCols(cells: Cell[], split = false) {
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const cols = mapArray(cells, this._regionIndexToColIndex);
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return split ? chunkify(cols, this.height) : cols;
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}
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rowsToRegions(cells: Cell[], split = false) {
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const regions = mapArray(cells, this._rowIndexToRegionIndex);
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return split ? chunkify(regions, this.regionCells) : regions;
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}
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colsToRegions(cells: Cell[], split = false) {
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const regions = mapArray(cells, this._colIndexToRegionIndex);
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return split ? chunkify(regions, this.regionCells) : regions;
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}
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getBlankPuzzle(): Puzzle {
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return Array(this.boardCells)
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.fill(null)
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.map((value) => ({ value }));
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}
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/**
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* Returns the remaining legal values given a set of taken values.
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*
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* @param taken a set of taken values
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*/
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getLegalValues(taken: Set<number>) {
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return this.legalValues.filter((value) => !taken.has(value));
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}
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/**
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* Returns which values are unavailable at a given location, looking at the
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* row, column, and region of the given cell index.
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*
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* @param cell
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* @param puzzle
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* @param regions
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*/
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getTakenValues(cell: number, puzzle: Puzzle, regions: Region[]) {
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const rows = this.regionsToRows(puzzle, true);
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const cols = this.regionsToCols(puzzle, true);
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const [row, col] = this.rowColFromRegionIndex(cell);
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const region = this.regionFromRegionIndex(cell);
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return getTakenValues(regions[region], rows[row], cols[col]);
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}
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/**
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* Returns whether a puzzle has only one solution.
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*
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* @param puzzle
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*/
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hasOneSolution(puzzle: Cell[]) {
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const optimistic = clone(puzzle);
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if (this.optimisticSolver(optimistic)) {
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return true;
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_checkInput(cells: Cell[][]) {
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if (cells.length !== this.values || cells[0].length !== this.values) {
|
||||
throw new Error(
|
||||
"Given cells array does not match regionWidth & regionHeight"
|
||||
);
|
||||
}
|
||||
return this.backTrackingSolver(optimistic, 2) === 1;
|
||||
}
|
||||
|
||||
/**
|
||||
* Generates a single-solution sudoku puzzle with
|
||||
*
|
||||
* @param clues the number of cells to have pre-filled
|
||||
*/
|
||||
generatePuzzle(clues: number) {
|
||||
const puzzle = this.getBlankPuzzle();
|
||||
this.backTrackingSolver(puzzle, 1, shuffle);
|
||||
// this takes a bit of time and the value may need to be cached
|
||||
getDLXHeader(
|
||||
cells: undefined | Cell[][] = undefined,
|
||||
randomSearch = false
|
||||
): [CNode, DNode[]] {
|
||||
if (cells) this._checkInput(cells);
|
||||
|
||||
if (clues === -1 || clues >= puzzle.length) return puzzle;
|
||||
const header = new CNode();
|
||||
header.name = "h";
|
||||
|
||||
const orig = clone(puzzle);
|
||||
const constraints = new Array<CNode>(this.values2 * 4)
|
||||
.fill(null!)
|
||||
.map((_, i) => {
|
||||
const column = new CNode();
|
||||
column.name = `${i}`;
|
||||
column.meta = i;
|
||||
return column;
|
||||
});
|
||||
|
||||
const toRemove = puzzle.length - clues;
|
||||
let removed: number[] = [];
|
||||
let removeNext: number[] = shuffle(puzzle.map((_, i) => i));
|
||||
// link together the header and constraint columns
|
||||
linkNodesLR([header, ...constraints]);
|
||||
|
||||
const remove = () => {
|
||||
const x = removeNext.shift() as any;
|
||||
removed.push(x);
|
||||
puzzle[x].value = null;
|
||||
};
|
||||
const candidates = randomSearch
|
||||
? shuffle(Array.from(this.candidates))
|
||||
: this.candidates;
|
||||
|
||||
const replace = () => {
|
||||
const x = removed.pop() as any;
|
||||
removeNext.push(x);
|
||||
puzzle[x].value = orig[x].value;
|
||||
};
|
||||
|
||||
const removeCell = () => {
|
||||
remove();
|
||||
if (this.hasOneSolution(puzzle)) {
|
||||
return true;
|
||||
}
|
||||
replace();
|
||||
return false;
|
||||
};
|
||||
|
||||
let fails = 0;
|
||||
while (removed.length < toRemove) {
|
||||
if (!removeCell()) {
|
||||
fails++;
|
||||
} else {
|
||||
console.log(`Removed ${removed.length} cells.`);
|
||||
fails = 0;
|
||||
}
|
||||
if (fails > removeNext.length) {
|
||||
fails = 0;
|
||||
Array(removed.length)
|
||||
.fill(null)
|
||||
.forEach(() => replace());
|
||||
shuffle(removeNext);
|
||||
}
|
||||
}
|
||||
|
||||
return puzzle;
|
||||
}
|
||||
|
||||
/**
|
||||
* Attempt to solve the puzzle "optimistically". Only sets values which are
|
||||
* certain, i.e. no guesses are made.
|
||||
*
|
||||
* Useful as a first pass.
|
||||
*
|
||||
* @param puzzle a region-ordered array of cells (each cell an object with
|
||||
* a `value` key.
|
||||
* @returns whether the puzzle was completely solved
|
||||
*/
|
||||
optimisticSolver(puzzle: Puzzle) {
|
||||
const regions = this.chunkRegions(puzzle);
|
||||
const rows = this.regionsToRows(puzzle, true);
|
||||
const cols = this.regionsToCols(puzzle, true);
|
||||
|
||||
const solve = (): boolean => {
|
||||
let foundValue = false;
|
||||
let foundEmpty = false;
|
||||
|
||||
for (let i = 0, len = puzzle.length; i < len; i++) {
|
||||
const cell = puzzle[i];
|
||||
if (!!cell.value) continue;
|
||||
foundEmpty = true;
|
||||
const region = this.regionFromRegionIndex(i);
|
||||
const [row, col] = this.rowColFromRegionIndex(i);
|
||||
const taken = getTakenValues(regions[region], rows[row], cols[col]);
|
||||
if (taken.size === this.regionCells - 1) {
|
||||
cell.value = this.getLegalValues(taken)[0];
|
||||
foundValue = true;
|
||||
const dlxRows: DNode[] = [];
|
||||
candidates.forEach(([i, row, col, region, val]) => {
|
||||
if (cells) {
|
||||
const exist = cells[row][col].value;
|
||||
if (exist && exist - 1 !== val) {
|
||||
// skip candidates matching this constraint's position, but not its value
|
||||
// the effect is the exisitng value is preserved in the output
|
||||
return;
|
||||
}
|
||||
}
|
||||
return foundValue && foundEmpty ? solve() : !foundEmpty;
|
||||
};
|
||||
|
||||
return solve();
|
||||
const meta = { row, col, region, value: val + 1 };
|
||||
const dlxRow = linkNodesLR(
|
||||
this.getConstraintIDs(val, row, col, region).map((id) =>
|
||||
addNodeToColumn(constraints[id], meta)
|
||||
)
|
||||
);
|
||||
dlxRows.push(dlxRow[0]);
|
||||
});
|
||||
|
||||
return [header, dlxRows];
|
||||
}
|
||||
|
||||
/**
|
||||
* Backtracking solver. Mutates the puzzle during solve but eventually returns
|
||||
* it to its initial state.
|
||||
*
|
||||
* @param puzzle see optimisticSolver
|
||||
* @param stopAfter stop looking after this many solutions
|
||||
* @param guessStrategy a function which takes an array of possible
|
||||
* values for a cell, and returns the same values (in any order)
|
||||
* @returns the number of solutions found
|
||||
*/
|
||||
backTrackingSolver(
|
||||
puzzle: Puzzle,
|
||||
stopAfter: number = -1,
|
||||
guessStrategy: (values: number[]) => number[] = (values: number[]) => values
|
||||
) {
|
||||
const regions = this.chunkRegions(puzzle);
|
||||
const rows = this.regionsToRows(puzzle, true);
|
||||
const cols = this.regionsToCols(puzzle, true);
|
||||
_baseBoard(): Cell[][] {
|
||||
// return a sudoku board with a random set of values in the first row
|
||||
// used in generateComplete for small speedup
|
||||
const firstRow = range(1, this.values + 1);
|
||||
shuffle(firstRow);
|
||||
return [
|
||||
firstRow.map((value) => ({ value })),
|
||||
...Array(this.values - 1)
|
||||
.fill(null)
|
||||
.map(() =>
|
||||
Array(this.values)
|
||||
.fill(0)
|
||||
.map((val) => ({ value: val > 0 ? val : null }))
|
||||
),
|
||||
];
|
||||
}
|
||||
|
||||
generateComplete() {
|
||||
const result = this._baseBoard();
|
||||
const [header] = this.getDLXHeader(result, true);
|
||||
|
||||
const callback = (solution: DNode[]) => {
|
||||
solution.forEach((node) => {
|
||||
const meta: NodeMeta = node.meta;
|
||||
result[meta.row][meta.col] = { value: meta.value };
|
||||
});
|
||||
// return the first solution
|
||||
return true;
|
||||
};
|
||||
|
||||
const dlx = new DLX(header, callback);
|
||||
|
||||
dlx.search();
|
||||
return result;
|
||||
}
|
||||
|
||||
generate(clues: number, attempts = Infinity, totalTime = Infinity) {
|
||||
const completed = this.generateComplete();
|
||||
|
||||
const [header, dlxRows] = this.getDLXHeader(); // complete header - no candidates removed
|
||||
|
||||
let solutions = 0;
|
||||
const solve = (): boolean => {
|
||||
for (let i = 0, len = puzzle.length; i < len; i++) {
|
||||
const cell = puzzle[i];
|
||||
if (!cell.value) {
|
||||
const region = this.regionFromRegionIndex(i);
|
||||
const [row, col] = this.rowColFromRegionIndex(i);
|
||||
const avail = guessStrategy(
|
||||
this.getLegalValues(
|
||||
getTakenValues(regions[region], rows[row], cols[col])
|
||||
)
|
||||
);
|
||||
for (let j = 0; j < avail.length; j++) {
|
||||
cell.value = avail[j];
|
||||
if (solve() && solutions === stopAfter) {
|
||||
return true;
|
||||
}
|
||||
cell.value = null;
|
||||
}
|
||||
return false;
|
||||
}
|
||||
}
|
||||
solutions++;
|
||||
return true;
|
||||
const dlx = new DLX(header, () => ++solutions >= 2);
|
||||
|
||||
const candidates: DNode[][][] = Array.from(Array(this.values), () =>
|
||||
Array.from(Array(this.values), () => Array(this.values))
|
||||
);
|
||||
dlxRows.forEach((node) => {
|
||||
const meta = node.meta;
|
||||
candidates[meta.row][meta.col][meta.value - 1] = node;
|
||||
});
|
||||
|
||||
// board positions which have been removed, in the order they've been removed
|
||||
const removed: Set<number> = new Set();
|
||||
const masked: DNode[] = [];
|
||||
|
||||
const hasOneSolution = () => {
|
||||
solutions = 0;
|
||||
dlx.search();
|
||||
return solutions === 1;
|
||||
};
|
||||
|
||||
solve();
|
||||
const mask = () => {
|
||||
// mask all DLX rows which are nullified by existing values
|
||||
for (let n = 0; n < this.values2; n++) {
|
||||
if (removed.has(n)) {
|
||||
continue;
|
||||
}
|
||||
const row = Math.floor(n / this.values);
|
||||
const col = n % this.values;
|
||||
const existValue = completed[row][col].value;
|
||||
const nodes = candidates[row][col];
|
||||
// console.log(row, col);
|
||||
// console.log(existValue);
|
||||
nodes.forEach((node) => {
|
||||
if (node.meta.value !== existValue) {
|
||||
// console.log(node.meta);
|
||||
// console.log("masking node");
|
||||
masked.push(node);
|
||||
maskRow(node);
|
||||
}
|
||||
});
|
||||
}
|
||||
};
|
||||
|
||||
return solutions;
|
||||
const unmask = () => {
|
||||
// unmask all DLX rows
|
||||
while (masked.length > 0) {
|
||||
unmaskRow(masked.pop()!);
|
||||
}
|
||||
};
|
||||
|
||||
const start = Date.now();
|
||||
const elapsed = () => Date.now() - start;
|
||||
|
||||
const removeable = Array.from(this.indexes);
|
||||
const attempt = () => {
|
||||
// attempt remove cells until 'clues' cells remain
|
||||
shuffle(removeable);
|
||||
for (let n = 0; n < this.values2; n++) {
|
||||
if (elapsed() > totalTime || this.values2 - removed.size == clues) {
|
||||
break;
|
||||
}
|
||||
|
||||
let toRemove = removeable[n];
|
||||
removed.add(toRemove);
|
||||
mask();
|
||||
|
||||
if (!hasOneSolution()) {
|
||||
removed.delete(toRemove);
|
||||
}
|
||||
|
||||
unmask();
|
||||
}
|
||||
};
|
||||
|
||||
while (
|
||||
this.values2 - removed.size > clues &&
|
||||
attempts > 0 &&
|
||||
elapsed() < totalTime
|
||||
) {
|
||||
// try to reach the clue goal up to `attempts` times or as long as
|
||||
// elapsed time is less than `totalTime`
|
||||
attempts--;
|
||||
removed.clear();
|
||||
attempt();
|
||||
}
|
||||
|
||||
removed.forEach((index) => {
|
||||
completed[Math.floor(index / this.values)][
|
||||
index % this.values
|
||||
].value = null;
|
||||
});
|
||||
return completed;
|
||||
}
|
||||
|
||||
solve(existing: Cell[][]): void {
|
||||
const [header] = this.getDLXHeader(existing);
|
||||
const callback = (solution: DNode[]) => {
|
||||
solution.forEach((node) => {
|
||||
const meta: NodeMeta = node.meta;
|
||||
existing[meta.row][meta.col] = { value: meta.value };
|
||||
});
|
||||
// return the first solution
|
||||
return true;
|
||||
};
|
||||
new DLX(header, callback).search();
|
||||
}
|
||||
}
|
||||
|
||||
@ -1,14 +1,14 @@
|
||||
import { Cell } from "./index";
|
||||
|
||||
function randInt(lower: number, upper: number) {
|
||||
return lower + Math.trunc(Math.random() * (upper - lower + 1));
|
||||
export function randInt(lower: number, upper: number) {
|
||||
return Math.floor(Math.random() * (upper - lower)) + lower;
|
||||
}
|
||||
|
||||
export function shuffle(arr: any[]) {
|
||||
export function shuffle<T>(arr: T[]) {
|
||||
const length = arr.length;
|
||||
let lastIndex = length - 1;
|
||||
const last = length;
|
||||
for (let i = 0; i < length; i++) {
|
||||
const rand = randInt(i, lastIndex);
|
||||
const rand = randInt(i, last);
|
||||
const tmp = arr[rand];
|
||||
|
||||
arr[rand] = arr[i];
|
||||
@ -17,8 +17,8 @@ export function shuffle(arr: any[]) {
|
||||
return arr;
|
||||
}
|
||||
|
||||
export function chunkify(arr: any[], chunkSize: number) {
|
||||
const chunks = Array(arr.length / chunkSize);
|
||||
export function chunkify<T>(arr: T[], chunkSize: number) {
|
||||
const chunks = Array<T[]>(arr.length / chunkSize);
|
||||
for (let i = 0, len = chunks.length; i < len; i++) {
|
||||
const start = i * chunkSize;
|
||||
chunks[i] = arr.slice(start, start + chunkSize);
|
||||
@ -27,7 +27,7 @@ export function chunkify(arr: any[], chunkSize: number) {
|
||||
}
|
||||
|
||||
export function range(start: number, end: number) {
|
||||
return Array(1 + end - start)
|
||||
return Array(end - start)
|
||||
.fill(null)
|
||||
.map((_, i) => start + i);
|
||||
}
|
||||
@ -57,3 +57,30 @@ export function addCellValuesToSet(set: Set<number>, cells: Cell[]) {
|
||||
});
|
||||
return set;
|
||||
}
|
||||
|
||||
export function prettyPrint(puzzle: Cell[][]) {
|
||||
let width = Math.sqrt(puzzle[0].length);
|
||||
let height = Math.sqrt(puzzle.length);
|
||||
|
||||
puzzle.forEach((row, i) => {
|
||||
let line = "";
|
||||
row.forEach(({ value: cell }, j) => {
|
||||
if (j > 0 && j % width == 0) {
|
||||
line += "| ";
|
||||
}
|
||||
line += ((cell ? cell : " ") + " ").padStart(3, " ");
|
||||
});
|
||||
|
||||
if (i > 0 && i % height == 0) {
|
||||
let divider = "";
|
||||
row.forEach((_, j) => {
|
||||
if (j > 0 && j % width == 0) {
|
||||
divider += " ";
|
||||
}
|
||||
divider += "-- ";
|
||||
});
|
||||
console.log(divider);
|
||||
}
|
||||
console.log(line);
|
||||
});
|
||||
}
|
||||
|
||||
@ -1,8 +1,15 @@
|
||||
const { SudokuMath } = require("./math");
|
||||
const { parentPort } = require("worker_threads");
|
||||
|
||||
const maths = {};
|
||||
|
||||
parentPort.on("message", ({ regionWidth, regionHeight, clues }) => {
|
||||
const math = new SudokuMath(regionWidth, regionHeight);
|
||||
const puzzle = math.generatePuzzle(clues);
|
||||
parentPort.postMessage([math, puzzle]);
|
||||
const math =
|
||||
maths[`${regionWidth}:${regionHeight}`] ||
|
||||
(maths[`${regionWidth}:${regionHeight}`] = new SudokuMath(
|
||||
regionWidth,
|
||||
regionHeight
|
||||
));
|
||||
const puzzle = math.generate(clues);
|
||||
parentPort.postMessage(puzzle);
|
||||
});
|
||||
|
||||
Loading…
Reference in New Issue
Block a user