可变数组交换(冒泡排序)

    // 可变数组交换(冒泡排序)    NSMutableArray *array = [NSMutableArray arrayWithObjects:@23, @56, @13, @67, @40, @33, nil];    for (int i = 0; i < [array count] - 1; i ++) {        for (int j = 0; j < [array count] - i - 1; j ++) {            if (NSOrderedDescending == [[array objectAtIndex:j] compare:[array objectAtIndex:j + 1]]) {                [array exchangeObjectAtIndex:j withObjectAtIndex:j + 1];            }        }    }        NSLog(@"%@", array);