Cod sursa(job #463108)

Utilizator gramatovici_paulGramatovici Paul gramatovici_paul Data 14 iunie 2010 16:41:11
Problema Fractii Scor 0
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.35 kb
Raporteaza aceasta sursa 
#include<stdio.h>
const int N=1<<20;
int e[N],i,j,n,s;
int main()
{
	freopen("fractii.in","r",stdin);
	freopen("fractii.out","w",stdout);
	scanf("%d",&n);
	for (i=1; i<=n; ++i)
		e[i]=i;
	for (i=2; i<=n; ++i)
		if (e[i]==i)
			for (j=1; j<=n; j+=i)
				e[j]=e[j]/i*(i-1);
	for (i=2; i<=n; ++i)
		s+=e[i]*2;
	printf("%d",s+1);
	return 0;
}