Cod sursa(job #2356346)

Utilizator AlbertSimaAlbert Sima Gabriel AlbertSima Data 26 februarie 2019 17:06:58
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.33 kb
Raporteaza aceasta sursa 
#include <bits/stdc++.h>
using namespace std;

ifstream f("ciur.in");
ofstream g("ciur.out");

bool p[2000001];
int n,i,j,k=1;
int main()
{
   f>>n;
   for(i=3;i<=n;i=i+2)
   {
       if(p[i]==0)
       {
            k++;
            for(j=i+i;j<=n ;j=j+i)
                p[j]=1;
       }
   }
   g<<k;
    return 0;
}