ios 冒泡排序和快速排序

#pragma marl - 排序算法 冒泡排序
-(NSMutableArray *) bullArr:(NSMutableArray *) arr{
for (int i = 0; i<arr.count; i++) {
    for (int j = 0; j<arr.count-1-i; j++) {
        if (arr[j] < arr[j+1]) {
            [arr exchangeObjectAtIndex:j withObjectAtIndex:j+1];
        }
    }
}
return arr;
}


#pragma marl - 排序算法 选择排序
-(NSMutableArray *) selectArr:(NSMutableArray *) arr{
    for (int i = 0; i<arr.count; i++) {
          for (int j = i+1; j < arr.count; j++) {
              if (arr[i] < arr[j]) {
               [arr exchangeObjectAtIndex:i withObjectAtIndex:j];
        }
    }
}
return arr;
}