Cod sursa(job #1503432)

Utilizator dcmionutIonut Deaconu dcmionut Data 16 octombrie 2015 04:58:49
Problema Fractii Scor 0
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.33 kb
Raporteaza aceasta sursa 
include <iostream>
using namespace std;
int main()
{
  long long int k = 0;
  long phi[1000];
  long n;
  cin>>n;
  for (long i = 1; i <= n; ++i)
    phi[i] = i - 1;
  for (long i = 2; i <= n; ++i)
    for (long j = 2 * i; j <= n; j += i)
      phi[j] -= phi[i];
  for(i = 1; i<=n; i++)
    k += phi[i];
  cout<<k + 1;
}