iOS 二维数组排序小算法

NSArray *tmp = @[@[@(1), @(2), @(3), @(4), @(5)],
                     @[@(6), @(7), @(8), @(9), @(10)],
                     @[@(11), @(12), @(13), @(14), @(15)],
                     @[@(16), @(17), @(18), @(19), @(20)],
                     @[@(21), @(22), @(23), @(24), @(25)]];

int count = [tmp count];
    
    for (int num = 0; num <= 2*(count-1); num++) { // 遍历总的次数
        NSMutableArray *tmpArray = [NSMutableArray array];
        for (int j=0; j<count; j++) {
            if ( (num-j)<0) { // 如果遍历的次数小于总行号, 直接跳出循环
                break;
            }
            if(num-j+1 > count){ // 如果越界, 则跳出本次循环
                continue;
            }
            [tmpArray addObject:tmp[num - j][j]];
        }
        NSLog(@"Array = %@", tmpArray);
    }