Giant For

It is known to us all that YY and LMY are mathematics lovers. They like to find and solve interesting mathematic problems together. Now LMY designs a game for matrix. There is a large matrix whose rows and columns are both not more than 1000000000. And there are three operations for the matrix:
1) add: Mark an element in the matrix. It is guaranteed that the element has not been marked before.
2) remove: Delete an element’s mark. It is guaranteed that the element has been marked before.
3) find: For a given element’s row and column, return a marked element’s row and column, where the marked element’s row and column are larger than the given element’s row and column respectively. If there are multiple solutions, return the element whose row is the smallest; and if there are still multiple solutions, return the element whose column is the smallest. If there is no solution, return -1.
LMY lets YY develop a program to solve the problem. Could you also develop a program to solve the problem?

The input consists of multiple test cases. For each test case, the first line contains only one integer n. n ≤ 200000. Each of the next n lines describes an operation. There is a blank line between two consecutive test cases.
End of input is indicated by a line containing a zero.

Start each test case with "Case #:" on a single line, where # is the case number starting from 1. For each “find” operation, output the result. The format is showed as sample output. There is a blank line between two consecutive test cases.

5
add 48 1
add 25 69
add 88 52
remove 25 69
add 23 89

10
add 47 23
find 66 83
find 27 73
add 84 97
find 10 58
remove 47 23
add 41 89
remove 41 89
find 65 68
add 25 41

0

Case 1:

Case 2:
-1
-1
84 97
84 97

2010 Asia Regional Tianjin Site —— Online Contest