Method init

app/src/main/java/solver/EightPuzzle.java:20–50

()

    };

    static void init() {
        if (ini) return;
        long time = System.currentTimeMillis();
        int[] arr = new int[9];
        Arrays.fill(prun, (byte) -1);
        prun[0] = 0;
        int c = 1;
        for (int d = 0; d < 24; d++) {
            //c = 0;
            for (int i=0; i<362880; i++)
                if (prun[i] == d) {
                    Utils.set11Perm(arr, i, 9);
                    for (int m=0; m<4; m++) {
                        System.arraycopy(arr, 0, pz, 0, 9);
                        for (int n = 0; n < 2; n++) {
                            int next = move(m);
                            if (next == -1) break;
                            next = Utils.get11Perm(pz, 9);
                            if (prun[next] < 0) {
                                prun[next] = (byte) (d + 1);
                                c++;
                            }
                        }
                    }
                }
            //Log.w("dct", d + 1 + "\t" + c);
        }
        time = System.currentTimeMillis() - time;
        Log.w("dct", "init "+time+"ms");
        ini = true;
    }

    private static int move(int m) {
        int pos = 0;