NSMutableArray *mArray = [NSMutableArray arrayWithObjects:@4,@5,@9,@2,@3,@3,@2,@7, nil];
   
    for (int i = 0; i<mArray.count-1; i++) {
        for (int j = 0; j<mArray.count - i-1; j++) {
            if (mArray[i] < mArray[i+1]) {
                NSInteger temp = [mArray[i+1]integerValue];
                mArray[i+1] = mArray[i];
                mArray[i] = [NSNumber numberWithInteger:temp];
            }
        }
    }
    
    
    for (int i = 0; i<mArray.count-1; i++) {
        for (int j = 0; j<mArray.count - i-1; j++) {
            if (mArray[j] < mArray[j+1]) {
                NSInteger temp = [mArray[j+1]integerValue];
                mArray[j+1] = mArray[j];
                mArray[j] = [NSNumber numberWithInteger:temp];
            }
        }
    }
    
    
    for (int i = 0; i<mArray.count-1; i++) {
        for (int j = i; j<mArray.count-1; j++) {
            if (mArray[j]<mArray[j+1]) {
                NSInteger temp = [mArray[j+1]integerValue];
                mArray[j+1] = mArray[j];
                mArray[j] = [NSNumber numberWithInteger:temp];
            }
        }
    }
    
    
    for (int i = 0; i<mArray.count-1; i++) {
        for (int j = i; j<mArray.count-1; j++) {
            if (mArray[i]<mArray[j+1]) {
                NSInteger temp = [mArray[j+1]integerValue];
                mArray[j+1] = mArray[i];
                mArray[i] = [NSNumber numberWithInteger:temp];
            }
        }
    }
    
    
   
    
    [mArray enumerateObjectsUsingBlock:^(id  _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
        NSLog(@"value %@",obj);
    }];
 

冒泡選擇排序