Cod sursa(job #247071)

Utilizator bixcabc abc bixc Data 22 ianuarie 2009 08:39:16
Problema Ciurul lui Eratosthenes Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.33 kb
#include<fstream.h>
 char v[2000001];
int main() {
 int s,n,i,j;
 ifstream f("ciure.in");
 ofstream g("ciure.out");

 f>>n;
 s=0;
 for (i=2;i<=n;i++)
     v[i]=0;
 for (i=2;i<=n;i++) {

     if (v[i]==0) {
	s=s+1;
	for(j=2*i;j<=n;j+=i) {
	   v[j]=1;
	   }
     }

 }
 g<<s;
 f.close();
 g.close();
 return 0;
 }