Cod sursa(job #972722)
Utilizator | Data | 12 iulie 2013 15:47:30 | |
---|---|---|---|
Problema | Fractii | Scor | 10 |
Compilator | cpp | Status | done |
Runda | Arhiva de probleme | Marime | 0.31 kb |
#include <fstream>
using namespace std;
ifstream f("fractii.in");
ofstream g("fractii.out");
int pr(int a, int b)
{
int r=b;
while(a%b!=0) {r=a%b; a=b; b=r;}
return r;
}
int main()
{
int n;
f>>n;
int k=2*n-1,i,j;
for(i=2;i<=n;i++) for(j=i+1;j<=n;j++) if(pr(i,j)==1) k+=2;
g<<k;
return 0;
}