UVa - 12459 - Bees' ancestors

#include <iostream>
#include <algorithm>
#include <cstdio>
#include <iomanip>
#include <vector>
#include <cmath>
#define Pi acos(-1)
using namespace std;

int main(){
    int g;
    long long ans;
    vector <long long> fib;
    while(cin >> g){
        if(g == 0)break;
        fib.push_back(0);
        fib.push_back(1);
        for(int i = 1; i <= g; i++){
            ans = fib[i-1] + fib[i];
            fib.push_back(ans);
        }
        cout << ans << endl;fib.clear();
    }

    return 0;
}