螺旋二维数组（矩阵）遍历

        int [][] arrays = {
                {6,7,8,9,10,11},
                {5,24,25,26,27,12},
                {4,23,34,35,28,13},
                {3,22,33,36,29,14},
                {2,21,32,31,30,15},
                {1,20,19,18,17,16},
        };
        int xBegin = 0;
        int xEnd = 5;
        int yBegin = 0;
        int yEnd = 5;
        while (true) {
            for (int i = yEnd; i >= yBegin; i--) {
                System.err.println(arrays[i][yBegin]);
            }
            xBegin++;
            for (int i = xBegin; i <=xEnd; i++) {
                System.err.println(arrays[yBegin][i]);
            }
            yBegin++;
            for (int i = yBegin; i <= yEnd; i++) {
                System.err.println(arrays[i][xEnd]);
            }
            xEnd--;
            for (int i = xEnd; i >= xBegin; i--) {
                System.err.println(arrays[yEnd][i]);
            }
            yEnd--;
            if (xBegin >= xEnd) {
                break;
            }
        }