用objective-c 实现常用算法（冒泡、选择、快速、插入）

下午研究了下用oc实现常用的算法，参考了一些资料后自己用代码检验了下，以下代码均测试可用。其中arr参数是一个可变数组，其中存的是NSNumber类型的数据，具体如下：

NSArray *arr = @[[NSNumber numberWithInt:10],[NSNumber numberWithInt:1],[NSNumber numberWithInt:3],[NSNumber numberWithInt:12],[NSNumber numberWithInt:22],[NSNumber numberWithInt:5],[NSNumber numberWithInt:33]];
NSMutableArray *oldArr = [[NSMutableArray alloc]initWithArray:arr];
NSLog(@"排序前:%@",oldArr);

一.冒泡排序

- (void)sort:(NSMutableArray *)arr
{
    for (int i = 0; i < arr.count; i++) {
        for (int j = 0; j < arr.count - i - 1;j++) {
            if ([arr[j+1]integerValue] < [arr[j] integerValue]) {
                int temp = [arr[j] integerValue];
                arr[j] = arr[j + 1];
                arr[j + 1] = [NSNumber numberWithInt:temp];
            }
        }
    }
    NSLog(@"冒泡排序后：%@",arr);
}

二.选择排序

- (void)sort:(NSMutableArray *)arr
{
    for (int i = 0; i < arr.count; i ++) {
        for (int j = i + 1; j < arr.count; j ++) {
            if ([arr[i] integerValue] > [arr[j] integerValue]) {
                int temp = [arr[i] integerValue];
                arr[i] = arr[j];
                arr[j] = [NSNumber numberWithInt:temp];
            }
        }
    }

    NSLog(@"选择排序后：%@",arr);
}

三.快速排序

- (void)quickSort:(NSMutableArray *)arr leftIndex:(int)left rightIndex:(int)right
{
    if (left < right) {
        int temp = [self getMiddleIndex:arr leftIndex:left rightIndex:right];
        [self quickSort:arr leftIndex:left rightIndex:temp - 1];
        [self quickSort:arr leftIndex:temp + 1 rightIndex:right];
    }
}

- (int)getMiddleIndex:(NSMutableArray *)arr leftIndex:(int)left rightIndex:(int)right
{
    int tempValue = [arr[left] integerValue];
    while (left < right) {
        while (left < right && tempValue <= [arr[right] integerValue]) {
            right --;
        }
        if (left < right) {
            arr[left] = arr[right];
        }

        while (left < right && [arr[left] integerValue] <= tempValue) {
            left ++;
        }
        if (left < right) {
            arr[right] = arr[left];
        }
    }
    arr[left] = [NSNumber numberWithInt:tempValue];
    return left;
}

四.插入排序

- (void)sort:(NSMutableArray *)arr
{
    for (int i = 1; i < arr.count; i ++) {
        int temp = [arr[i] integerValue];

        for (int j = i - 1; j >= 0 && temp < [arr[j] integerValue]; j --) {
            arr[j + 1] = arr[j];
             arr[j] = [NSNumber numberWithInt:temp];
        }


    }
    NSLog(@"插入排序后：%@",arr);
}