Cod sursa(job #1504704)

Utilizator BrinzeiAdrian Brinzei Brinzei Data 18 octombrie 2015 02:58:04
Problema Fractii Scor 0
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.34 kb
Raporteaza aceasta sursa 
#include <fstream>

using namespace std;
ifstream f("fractii.in");
ofstream o("fractii.out");
int main()
{
    int s=0,v[10000001],n;
    f>>n;
    for(int i=1;i<=n;i++)
        v[i]=i-1;
    for(int i=1;i<=n;i++){
        s = v[i]*2*1LL + s;

    for(int j=2*i;j<=n;j+=i)
        v[j]-=v[i];
    }
    o<< ++s;
    return 0;
}