Cod sursa(job #2231139)

Utilizator Y.MalmsteenB.P.M. Y.Malmsteen Data 13 august 2018 09:23:40
Problema Sum Scor 90
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.54 kb
#include <fstream>

using namespace std;
const int NMAX = 100000;

ifstream f("sum.in");
ofstream g("sum.out");

int Euler[NMAX + 1];

int main()
{
    int N, X;
    //
    for(int i = 2; i <= NMAX; i++)
        Euler[i] = i;
    for(int i = 2; i <= NMAX; i++)
    {
        if(Euler[i] == i)
            for(int j = i; j <= NMAX; j += i)
                Euler[j] = Euler[j] / i * (i - 1);
    }
    //
    f >> N;
    while(N--)
    {
        f >> X;
        g << 2LL * X * Euler[X] << '\n';
    }
    return 0;
}