Cod sursa(job #1068732)

Utilizator forever16Alex M forever16 Data 28 decembrie 2013 18:16:26
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.34 kb
Raporteaza aceasta sursa 
#include <fstream>
using namespace std;
bool a[2000001];
int main()

{   int n, i, j, s=0;
    ifstream f("ciur.in");
    ofstream g("ciur.out");
    f>>n;

    for (i=2; i<=n;i++)
    a[i]=1;
    for (i=2;i<=n;i++) {
            if (a[i]) { s++;
    for (j=i+i; j<=n; j+=i) a[j]=0;
            } }
     g<<s;
     return 0;
    }