Cod sursa(job #192956)

Utilizator ProcopliucProcopliuc Adrian Procopliuc Data 1 iunie 2008 16:46:08
Problema Fractii Scor 30
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.31 kb
Raporteaza aceasta sursa 
# include <stdio.h>
long int i,j,n,s,a[1000010];
int main ()
{
freopen ("fractii.in","r",stdin);
freopen ("fractii.out","w",stdout);
scanf ("%li",&n);
for (i=0;i<=n;i++)
a[i]=i-1;
for (i=2;i<=n;i++)
for (j=i*2;j<=n;j=j+i)
a[j]=a[j]-a[i];
for (i=1;i<=n;i++)
s=s+a[i];
printf ("%li",2*s+1);
return 0;
}