Cod sursa(job #1150237)

Utilizator radu_cebotariRadu Cebotari radu_cebotari Data 22 martie 2014 18:36:32
Problema Sum Scor 85
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.55 kb
#include<fstream>
#include<iostream>
using namespace std;
long long phi[1000000],sum[1000000];

void solve()
{

    long long i,j;
    for(i = 1 ; i<=100001 ; i++)
        phi[i] = i-1;
    for(i = 2 ; i <= 100001 ;i++)
        for( j = 2*i ; j <= 100001 ; j+=i)
            phi[j] -= phi[i];

}
int main()
{
    ifstream in("sum.in");
    ofstream out("sum.out");
    long long T,n;
    in>>T;
    solve();
    for(; T ; --T )
    {
    in>>n;
    out<<2*n*phi[n]<<"\n";
    }
    in.close();
    out.close();
    return 0;
}