Cod sursa(job #1932938)

Utilizator mariodinudinu mario gabriel mariodinu Data 20 martie 2017 11:10:33
Problema Fractii Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.3 kb
Raporteaza aceasta sursa 
#include <fstream>
using namespace std;
int v[1000001],n,i,j;
unsigned long long r;
ifstream in("fractii.in");
ofstream out("fractii.out");
int main()
{
in>>n;
for(i=2;i<=n;i++)
    v[i]=i-1;
for(i=2;i<=n;i++)
{
    r+=v[i];
    for(j=i+i;j<=n;j=j+i)
    v[j]-=v[i];
}
r*=2;
out<<r+1;
}