Cod sursa(job #1885143)

Utilizator usureluflorianUsurelu Florian-Robert usureluflorian Data 19 februarie 2017 17:37:12
Problema Fractii Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.32 kb
Raporteaza aceasta sursa 
#include <fstream>
using namespace std;
ifstream f ("fractii.in");
ofstream g ("fractii.out");
int v[1000009],n,i,j;
unsigned long long t;
int main()
{
    f>>n;
    for(i=2;i<=n;i++) v[i]=i-1;
    for(i=2;i<=n;i++)
    {
        t+=v[i];
        for(j=i+i;j<=n;j=j+i) v[j]-=v[i];
    }
    t*=2;
    g<<t+1;
}