Cod sursa(job #798821)
Utilizator | Data | 17 octombrie 2012 13:20:56 | |
---|---|---|---|
Problema | Fractii | Scor | 0 |
Compilator | cpp | Status | done |
Runda | Arhiva de probleme | Marime | 0.29 kb |
#include<fstream>
using namespace std;
int i,j,n,s,a[1000001];
int main()
{
ifstream f("fractii.in");
ofstream g("fractii.out");
f >> n;
for (i=1;i<=n;i++)
a[i]=n-1;
s=1;
for (i=1;i<=n;i++)
{
for (j=2*i;j<=n;j+=i)
a[j]-=a[i];
s+=a[i];
}
g << s;
return 0;
}