iOS 排序 和数组比较算法

/*  排揎算法 升序 降序  */

- (NSMutableArray *)arrPaiXufrom:(NSMutableArray *)arr sheng:(BOOL)sheng

{

    for (int  i = 0; i < arr.count; i++)

    {

        for (int j = i+1; j < arr.count; j++)

        {

            NSNumber  *num = arr[i];

            if (sheng)

            {

                // 升序

                if (arr[i] > arr[j])

                {

                    arr[i] = arr[j];

                    arr[j] = num;

                }

            }

            else

            {

                // 降序

                if (arr[i] < arr[j])

                {

                    arr[i] = arr[j];

                    arr[j] = num;

                }

            }

        }

    }

    NSLog(@"%@",arr);

    return arr;

}


/*  一个数组包含有另一个数组并返回下标  没有为空*/

- (NSMutableArray *)arrfrom:(NSMutableArray *)arr  subArr:(NSMutableArray *)subArr

{

    NSMutableArray *indexArr= @[].mutableCopy;

    for (int  i = 0; i < arr.count; i++)

    {

        for (int j = 0; j