一个常见的删除数组元素的bug

    NSMutableArray *array = [NSMutableArrayarrayWithObjects:@"1",@"2",@"3",@"4",nil];

   for(int i =0;i < [array count];i++)

    {

        [arrayremoveObjectAtIndex:i];

    }

    NSLog(@"array = %@",array);

array = (

    2,

    4

)

 NSMutableArray *array = [NSMutableArrayarrayWithObjects:@"1",@"2",@"3",@"4",nil];

   for(int i =0;i < [array count];i++)

    {

        [arrayremoveLastObject];

    }

    NSLog(@"array = %@",array);

array = (

    1,

    2

)

    NSMutableArray *array = [NSMutableArrayarrayWithObjects:@"1",@"2",@"3",@"4",nil];

   for(int i =0;i < [array count];i++)

    {

        [arrayremoveAllObjects];

    }

    NSLog(@"array = %@",array);

array = (

)