In this problem, you will create a program that reads a positive integer N from standard input, calculates the sum of all integers from 1 to N, and displays the result to standard output.

Problem Overview

Create a program that inputs a positive integer N and calculates the sum from 1 to N.

Input Format

Receive 1 line of input:

• Positive integer N (1 or greater)

Output Format

Output in the following format:

Sum from 1 to [N]: [sum]

Example

Input: 5
Output: Sum from 1 to 5: 15
(Calculation: 1+2+3+4+5=15)