#include<bits/stdc++.h> using namespace std; int sum(int n,int m){ int sum=0; for(int i=n;i<=m;i++){ sum+=i; } return sum; } int main(){ int c; c=sum(1,10); cout<<c<<endl; c=sum(20,30); cout<<c<<endl; c=sum(35,45); cout<<c<<endl; return 0; }