Cod sursa(job #223534)

Utilizator roberta_raileanuRoberta Raileanu roberta_raileanu Data 28 noiembrie 2008 19:10:03
Problema Fractii Scor 0
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.33 kb
Raporteaza aceasta sursa 
#include<stdio.h>
int main()
{
	int n,i,j,s,e[100];
	s=1;
	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=i;j<=n;j+=i)
				e[j]=e[j]/i*(i-1);
		}
	}
	for(i=2;i<=n;i++)
		s=s+2*e[i];
	printf("%d",s);
}