Cod sursa(job #397984)
Utilizator | George Tudor meandyou01 | Data | 17 februarie 2010 19:54:34 |
---|---|---|---|
Problema | Fractii | Scor | 30 |
Compilator | cpp | Status | done |
Runda | Arhiva de probleme | Marime | 0.46 kb |
#include<fstream>
using namespace std;
ifstream fin("fractii.in");
ofstream fout("fractii.out");
long n,i,s=1,j,p,d,putere,putere2;
int main()
{fin>>n;
for(i=2;i<=n;i++)
{ j=i;p=1;d=2;
while(j!=1)
{ putere=0;
putere2=1;
while(j%d==0)
{ putere++;
putere2*=d;
j=j/d;
}
if(putere!=0)p=p*(d-1)*(putere2/d);
if(d==2)d++;else d+=2;
}
s+=p*2;
}
fout<<s;
fin.close();
fout.close();
return 0;
}