Cod sursa(job #1687243)

Utilizator infosharkOpris Catalin infoshark Data 12 aprilie 2016 18:54:24
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.34 kb
#include <iostream>
#include <fstream>
using namespace std;
bool v[2000001];
ifstream in("ciur.in");
ofstream out("ciur.out");

int main()
{int n,c=0;

in>>n;
for(int i=2; i<=n; ++i)
{
    if(v[i]==0)
    {
        c++;
        for(int j=i*2; j<=n; j+=i)
        {
            v[j]=1;

        }
    }
}
out<<c;
return 0;
}