Cod sursa(job #283235)

Utilizator brainwashed20Alexandru Gherghe brainwashed20 Data 18 martie 2009 21:27:00
Problema Fractii Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.31 kb
Raporteaza aceasta sursa 
#include<stdio.h>

int main()
{
 freopen("fractii.in","r",stdin);
 freopen("fractii.out","w",stdout);
 long long n,nr,a[1000001],i,j;
 scanf("%lld",&n);
 for(i=1; i<=n; i++) a[i]=i-1;
 for(i=1; i<=n; i++)
 {
  for(j=2*i; j<=n; j+=i) a[j]=a[j]-a[i];
  nr+=a[i];
 }
 printf("%lld",nr*2+1);
 return 0;
}