Cod sursa(job #638139)

Utilizator danieladDianu Daniela danielad Data 20 noiembrie 2011 19:07:20
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.32 kb
#include <cstdlib>
#include <iostream>
#include<fstream>

using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
bool prim[2000002];

int main(){
  int n,nr=0;
  f>>n;
  for(int i=2;i<=n;i++)
  if(prim[i]==0){
    nr++;
    for(int j=i;j<=n;j=j+i)
    prim[j]=1;
  }
  g<<nr;
  return 0;
}