Before you begin, you should try this problem! AVL Tree

This problem is simple. Initially, there is a list and it's empty. Then you are given four types of query.

1. Insert data to the list
2. Remove data from the list
3. Print an index (1-based) from a specified data after the list was sorted ascendingly
4. Print data from a specified index (1-based) after the list was sorted ascendingly

Input

Input contains several lines. Each line follows one of these formats.
1 n: Insert n (0 ≤ n ≤ 2³¹ - 1) to the list
2 n: Remove n from the list. If n was not found, do nothing
3 n: Print n's index (1-based) after the list was sorted ascendingly
4 i: Print data on i-th index (1-based) after the list was sorted ascendingly (0 ≤ i ≤ 2³¹ - 1)
-1: End of input

Output

For each query 3, print n's index in one line. If n was not found, just print -1
For each query 4, print data on i-th index in one line. If the index is not valid, just print -1

Example

Input:
3 20
-1

Output:
-1