Cod sursa(job #2107637)
Utilizator | Data | 17 ianuarie 2018 16:41:05 | |
---|---|---|---|
Problema | Fractii | Scor | 10 |
Compilator | cpp | Status | done |
Runda | Arhiva de probleme | Marime | 0.52 kb |
#include <iostream>
#include <cstdlib>
#include <fstream>
using namespace std;
int gcd(int u, int v) {
while ( v != 0) {
int r = u % v;
u = v;
v = r;
}
return u;
}
int f(int n){
int s = 0;
for(int i=1;i<=n;i++)
if(gcd(i,n)==1)
s+=2;
return s;
}
int main()
{
int N=-1, n;
ifstream myfile("fractii.in");
myfile >> n;
for(int i=1; i<=n;i++)
N+=f(i);
ofstream f("fractii.out");
f << N;
myfile.close();
f.close();
}