Cod sursa(job #1712032)

Utilizator murariu_sebaMurariu Sebastian murariu_seba Data 1 iunie 2016 20:20:16
Problema Fractii Scor 30
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.33 kb
Raporteaza aceasta sursa 
#include <fstream>
using namespace std;
int s[1000001],n,i,j,r;
ifstream in("fractii.in");
ofstream out("fractii.out");
int main()
{
    in>>n;
    for(i=2; i<=n; i++)
        s[i]=i-1;
    for(i=2; i<=n; i++)
    {
        r=r+s[i];
        for(j=i+i; j<=n; j=j+i)
            s[j]=s[j]-s[i];
    }
    out<<2*r+1;
}