#include<bits/stdc++.h>
using namespace std;
int main(){
	long long a=0;
	for(int i=1;i<=100;i++){
		a=a+i;
	}
	cout<<a;
	return 0;
} 
/**************************************************************
	Problem: 1053
	User: hongjiachen
	Language: C++
	Result: Wrong Answer
****************************************************************/