#include<bits/stdc++.h> 
using namespace std;
int main(){
    int s=100,n=0;
    while(s>=1){
      n=s+n;
      s=s-3;
    } cout<<n;
    return 0;
}
/**************************************************************
	Problem: 1053
	User: lijinkai
	Language: C++
	Result: Accepted
	Time:4 ms
	Memory:2072 kb
****************************************************************/