Cod sursa(job #1333012)

Utilizator ggokGeri Gokaj ggok Data 2 februarie 2015 17:55:17
Problema Ciurul lui Eratosthenes Scor 20
Compilator cpp Status done
Runda Arhiva educationala Marime 0.32 kb
Raporteaza aceasta sursa 
#include <iostream>
#include <fstream>
using namespace std;
int a[2000001];
int counter;
int main()
{
    freopen("ciur.in","r",stdin);
    freopen("ciur.out","w",stdout);
int N;
cin>>N;
for(int x=2;x<=N;x++){
    if(!a[x])
    counter++;
    for(int y=2;y<=N;y++)
    a[x*y]=1;
}
cout<<counter;
    return 0;
}