Cod sursa(job #2266203)

Utilizator ralfd123Amariei Andrei ralfd123 Data 22 octombrie 2018 14:45:34
Problema Ciurul lui Eratosthenes Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.34 kb
#include <fstream>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");

int n,v[2000000],nrp;

int main()
{   f>>n;

    for(int i=2;i<=n/2;++i)
        if( v[i] == 0 )
            for(int j=i+i;j<=n;j+=i) v[j]=1;

    for(int i=2;i<=n/2;++i)
        if( v[i] == 0 ) nrp++;

    g<<nrp;

g.close();
return 0;
}