### Hello World!

Time Limit: 1000 ms Memory Limit: 65536 KiB

#### Problem Description

We know that Ivan gives Saya three problems to solve (Problem F), and this is the first problem.
We need a programmer to help us for some projects. If you show us that you or one of your friends is able to program, you can pass the first hurdle.
I will give you a problem to solve. Since this is the first hurdle, it is very simple.”
We all know that the simplest program is the “Hello World!” program. This is a problem just as simple as the “Hello World!”
In a large matrix, there are some elements has been marked. For every marked element, return a marked element whose row and column are larger than the showed 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 -1.
Saya is not a programmer, so she comes to you for help
Can you solve this problem for her?

#### Input

The input consists of several test cases.
The first line of input in each test case contains one integer N (0<N1000), which represents the number of marked element.
Each of the next N lines containing two integers r and c, represent the element’s row and column. You can assume that 0<r, c300. A marked element can be repeatedly showed.
The last case is followed by a line containing one zero.

#### Output

For each case, print the case number (1, 2 …), and for each element’s row and column, output the result. Your output format should imitate the sample output. Print a blank line after each test case.

#### Sample Input

3
1 2
2 3
2 3

0

#### Sample Output

Case 1:
2 3
-1 -1
-1 -1

#### Source

2010年山东省第一届ACM大学生程序设计竞赛