数独求解器的回溯算法

Question

以下是我称之为回溯的情况。

outerloop: for (int k = 1; k < 11; k++) {
                    if (k == 10) {
                        int[][] fixed = backtrack(table, empties);
                        if(fixed==null){
                            return null;
                        }
                        return Sudokusolution(fixed, 9, 9);
                    }

其中k是我试图插入空位的数字。

这是我的回溯算法。堆栈孔是最初为空的数组的索引。

public static int[][] backtrack(int[][] goback, Stack<Integer> holes) {
    int a;
    int b;
    int x;
    ArrayList<Integer> well = new ArrayList<Integer>();
    outerloop2: while (!holes.isEmpty()) {
        b = holes.pop();
        a = holes.pop();
        x = goback[a][b];
        System.out.println(x);
        if (a < 3 && b < 3) {
            for (int row = 0; row < 3; row++) {
                for (int col = 0; col < 3; col++) {
                    well.add(goback[a][b]);
                }
            }
        }
        if (a < 3 && b > 2 && b < 6) {
            for (int row = 0; row < 3; row++) {
                for (int col = 3; col < 6; col++) {
                    well.add(goback[a][b]);
                }
            }
        }
            if (a < 3 && b > 5) {
                for (int row = 0; row < 3; row++) {
                    for (int col = 6; col < 9; col++) {
                        well.add(goback[a][b]);
                    }
                }
            }
            if (a > 2 && a < 6 && b < 3) {
                for (int row = 3; row < 6; row++) {
                    for (int col = 0; col < 3; col++) {
                        well.add(goback[a][b]);
                    }
                }
            }
            if (a > 2 && a < 6 && b > 2 && b < 6) {
                for (int row = 3; row < 6; row++) {
                    for (int col = 3; col < 6; col++) {
                        well.add(goback[a][b]);
                    }
                }
            }
            if (a > 2 && a < 6 && b > 5) {
                for (int row = 3; row < 6; row++) {
                    for (int col = 6; col < 9; col++) {
                        well.add(goback[a][b]);
                    }
                }
            }

            if (a > 5 && b < 3) {
                for (int row = 6; row < 9; row++) {
                    for (int col = 0; col < 3; col++) {
                        well.add(goback[a][b]);
                    }
                }
            }
            if (a > 5 && b > 2 && b < 6) {
                for (int row = 6; row < 9; row++) {
                    for (int col = 3; col < 6; col++) {
                        well.add(goback[a][b]);
                    }
                }
            }
            if (a > 5 && b > 5) {
                for (int row = 6; row < 9; row++) {
                    for (int col = 6; col < 9; col++) {
                        well.add(goback[a][b]);
                    }
                }
            }
            innerloop: for (int i = x + 1; i < 1; i++) {
                if (i == 10) {
                    continue outerloop2;
                }
                goback[a][b] = i;
                for (int l = b + 1; l < 9; l++) {
                    if (i == goback[a][l]) {
                        goback[a][b] = 0;
                        continue innerloop;
                    }
                }
                for (int m = b - 1; m > -1; m--) {
                    if (i == goback[a][m]) {
                        goback[a][b] = 0;
                        continue innerloop;
                    }
                }
                for (int n = a + 1; n < 9; n++) {
                    if (i == goback[n][b]) {
                        goback[a][b] = 0;
                        continue innerloop;
                    }
                }
                for (int o = a - 1; o > -1; o--) {
                    if (i == goback[o][b]) {
                        goback[a][b] = 0;
                        continue innerloop;
                    }
                }
                if (well.contains(i)) {
                    goback[a][b] = 0;
                    continue innerloop;
                }
                return goback;
            }
        }


    return null;
}

感谢任何帮助。谢谢！