Cod sursa(job #2495624)

Utilizator TheRealGamerFat Vlad TheRealGamer Data 19 noiembrie 2019 18:19:41
Problema Fractii Scor 0
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 0.27 kb
Raporteaza aceasta sursa 
#include <iostream>
#include <fstream>
using namespace std;

ifstream in("fractii.in");
ofstream out("fractii.out");

int main(){
    long long int n, i, k = 1;
    in>>n;
    for(i = 1; i <= n; i++){
        k += i - 1;
    }
    out<<2 * k - 1;
    return 0;
}