Cod sursa(job #1829258)

Utilizator medicinedoctoralexandru medicinedoctor Data 14 decembrie 2016 18:22:09
Problema Fractii Scor 10
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.35 kb
Raporteaza aceasta sursa 
#include <fstream>

using namespace std;

ifstream cin("fractii.in");
ofstream cout("fractii.out");

int gcd(int a, int b)
{
    if (!b) return a;
    return gcd(b, a % b);
}

main()
{
    int n,c;
    cin >> n;
    c=1;
    for (int i=1; i<=n; i++)
        for (int j=i+1; j<=n; j++)
            if (gcd(j,i)==1) c+=2;
    cout << c;
}