Cod sursa(job #1113111)

Utilizator superalin98Hassan Alin Ali superalin98 Data 20 februarie 2014 12:37:22
Problema Ciurul lui Eratosthenes Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 0.34 kb
#include <fstream>

using namespace std;
ifstream cin("ciur.in");
ofstream cout("ciur.out");
int a[2000000];
int main()
{
    int n,nr=0;
    cin>>n;
    for(int i = 2;i<=n;i++)
    {
        if(a[i]==0)
        {
            nr++;
            for(int j = i+i;j<=n;j+=i)
                a[j]= 1;
        }
    }
    cout<<nr;
}