Cod sursa(job #2218909)

Utilizator Ioana_GaborGabor Ioana Ioana_Gabor Data 6 iulie 2018 13:26:17
Problema Sum Scor 95
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.54 kb

#include <iostream>
#include <fstream>
#define MAX 100000

using namespace std;

int phi[MAX+1];

void calculeaza_phi() {
    for(int i = 2; i <= MAX; i++)
        phi[i] = i;

    for(int i = 2; i <= MAX; i++)
        if(phi[i] == i)
            for(int j = i; j <= MAX; j += i)
                phi[j] = phi[j] / i * (i - 1);
}

int main() {
    ifstream f("sum.in");
    ofstream g("sum.out");
    int n,x;
    f>>n;
    calculeaza_phi();
    for(int i=1;i<=n;i++) {
        f>>x;
        g<<2LL*phi[x]*x<<'\n';
    }

    f.close();
    g.close();
}