#include<iostream>
using namespace std;
int main()
{
    while(1)
    {
	int m,n,x,sum(0);
	cout<<"put two num"<<endl;
	cin>>m>>n;
	if(m==n)
	{
	    return 0;
	 }
	if(m<n)
	{
            x=m;
	    m=n;
	    n=x;
	}
	for(int i=n;i<=m;i++)
	{
	    sum=sum+i;
	}
	    cout<<"n to m sum is "<<sum<<endl;
	}
    return 0;
}