Cod sursa(job #396594)

Utilizator deiosxHalalai Tudor Andrei deiosx Data 15 februarie 2010 17:17:42
Problema Fractii Scor 0
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.31 kb
Raporteaza aceasta sursa 
#include <stdio.h>
FILE *f=fopen("fractii.in","r");
FILE *g=fopen("fractii.out","w");
int v[1000001];
int main()
{
int n,i,j,e,ax,d;
long long nr;
fscanf(f,"%ld",&n);
nr=0;
for (i=2;i<=n;i++)
{
v[i]=v[i]+i-1;
for (j=2*i;j<=n;j+=i)
v[j]-=v[i];
nr+=v[i];
}
nr=nr*2+1;
fprintf(f,"%d",nr);
return 0;
}