Cod sursa(job #692890)

Utilizator g0dlik3taygun agiali g0dlik3 Data 26 februarie 2012 20:36:37
Problema Fractii Scor 100
Compilator c Status done
Runda Arhiva de probleme Marime 0.33 kb
Raporteaza aceasta sursa 
#include <stdio.h>

int main () {
long long int n,j,k,i,p[1000000];
freopen("fractii.in","r",stdin);
freopen("fractii.out","w",stdout);

scanf("%Ld ",&n);
k=0;
for (i=1;i<=n;i++) p[i]=i;

for (i=2;i<=n;i++)
	if (p[i]==i) 
		for (j=i;j<=n;j+=i) {p[j] /=i;
					p[j]*=(i-1);}
for (i=1;i<=n;i++)
k=k+p[i];
printf("%Ld \n",k*2 -1);
return 0;
}