Can you write a computer program that can compute such sums really quickly?

Problem

Given two integers n and m, you should compute the sum of all the integers from n to m. In other words, you should compute

Σ	m	i     =     n + (n + 1) + (n + 2) + ... + (m - 1) + m
	i = n

Input

The first line contains the number of scenarios. Each scenario consists of a line containing the numbers n and m (-10⁹ ≤ n ≤ m ≤ 10⁹).

Output

The output for every scenario begins with a line containing "Scenario #i:", where i is the number of the scenario starting at 1. Then print the sum of all integers from n to m. Terminate the output for the scenario with a blank line.

Sample Input

3
1 100
-11 10
-89173 938749341

Sample Output

Scenario #1:
5050

Scenario #2:
-11

Scenario #3:
440625159107385260