Cod sursa(job #1205194)

Utilizator tudorv96Tudor Varan tudorv96 Data 5 iulie 2014 17:23:27
Problema Sum Scor 85
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.51 kb
#include <fstream>
#include <cstdio>
using namespace std;

ofstream fout ("sum.out");

const int N = 1e5 + 5;

long long phi[N], t, n;

int main() {
    freopen ("sum.in", "r", stdin);
    for (int i = 2; i < N; ++i)
        phi[i] = i;
    for (int i = 2; i < N / 2; ++i)
        if (phi[i] == i)
            for (int j = i; j < N; j += i)
                phi[j] -= phi[j] / i;
    scanf ("%d", &t);
    while (t--) {
        scanf ("%d", &n);
        fout << 2LL * n * phi[n] << "\n";
    }
}