Write a program that asks the user for a number n and prints the sum of the numbers 1 to n.

Input : 

100

Output : 

The sum of numbers from 1 to 100 is : 5050

Program:

#include<iostream>

using namespace std;

//Write a program that asks the user for a number n and prints the sum of the numbers 1 to n.

int main()

{

    int n,sum;

    cout<<"Enter the number : ";

    cin>>n;

    sum=(n)*(n+1)/2;

    cout<<"The sum of numbers from 1 to "<<n<<" is : "<<sum;

    return 0;

}