Cod sursa(job #2084780)

Utilizator Cpt.TropicalOlaru Valentin Alexandru Cpt.Tropical Data 9 decembrie 2017 11:54:21
Problema Ciurul lui Eratosthenes Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 0.35 kb
Raporteaza aceasta sursa 
#include <iostream>
#include <fstream>
using namespace std;
ifstream fin ("ciur.in");
ofstream fout ("ciur.out");

int a[2000000];
int main() {
int b,c=0,aux;
fin>>b;
for(int i=2;i<=b;i++)
{
    if(a[i]==0)
    {
        c++;
        for(int j=i*2;j<=b;j+=i)
        {
            a[j]=1;
        }

    }
}
fout<<c;
return 0;
}