Cod sursa(job #1426053)

Utilizator ursu_stefanUrsu Stefan ursu_stefan Data 28 aprilie 2015 21:34:02
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 n,nr;
short int prim[2000000];
int main()
{
    fin>>n;;
    for(int i=2;i<=n;i++)
    {
        if(!prim[i])
            nr++;
        for(int j=2*i;j<=n;j=j+i)
            prim[j]=1;
    }
    fout<<nr;
    return 0;
}