104.js

function solveSudoku(board) {
    function isValid(board, row, col, num) {
        for (let i = 0; i < 9; i++) {
            if (board[row][i] === num || board[i][col] === num || board[row - row % 3 + Math.floor(i / 3)][col - col % 3 + i % 3] === num) {
                return false;
            }
        }
        return true;
    }

    function solve() {
        for (let row = 0; row < 9; row++) {
            for (let col = 0; col < 9; col++) {
                if (board[row][col] === 0) {
                    for (let num = 1; num <= 9; num++) {
                        if (isValid(board, row, col, num)) {
                            board[row][col] = num;
                            if (solve()) {
                                return true;
                            }
                            board[row][col] = 0;
                        }
                    }
                    return false;
                }
            }
        }
        return true;
    }

    if (solve()) {
        return board;
    }
    return "No solution exists";
}

// Ejemplo de uso
const sudokuBoard = [
    [5, 3, 0, 0, 7, 0, 0, 0, 0],
    [6, 0, 0, 1, 9, 5, 0, 0, 0],
    [0, 9, 8, 0, 0, 0, 0, 6, 0],
    [8, 0, 0, 0, 6, 0, 0, 0, 3],
    [4, 0, 0, 8, 0, 3, 0, 0, 1],
    [7, 0, 0, 0, 2, 0, 0, 0, 6],
    [0, 6, 0, 0, 0, 0, 2, 8, 0],
    [0, 0, 0, 4, 1, 9, 0, 0, 5],
    [0, 0, 0, 0, 8, 0, 0, 7, 9]
];

console.log(solveSudoku(sudokuBoard));