eolymp
bolt
Try our new interface for solving problems
Məsələlər

Gauß in Elementary School

Gauß in Elementary School

Zaman məhdudiyyəti 1 saniyə
Yaddaşı istafadə məhdudiyyəti 64 MiB

Johann Carl Friedrich Gauß(1777-1855) was one of the most important German mathematicians . For those of you who remember the Deutsche Mark, a picture of him was printed on the 10,-DM bill. In elementary school, his teacher J. G. Buttner tried to occupy the pupils by making them add up the integers from 1 to 100. The young Gauß surprised everybody by producing the correct answers (5050) within seconds.

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

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

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

Giriş verilənləri

The first line contains the number of scenarios. Each scenario consists of a line containing the numbers n and m (-10^9nm 10^9).

Çıxış verilənləri

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.

Nümunə

Giriş verilənləri #1
3
1 100
-11 10
-89173 938749341
Çıxış verilənləri #1
Scenario #1:
5050

Scenario #2:
-11

Scenario #3:
440625159107385260