Cod sursa(job #1588488)

Utilizator dan.andreescdan andr dan.andreesc Data 3 februarie 2016 09:28:27
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.32 kb
Raporteaza aceasta sursa 


#include <fstream>

using namespace std;

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

bool v[2000001];
int i,n,j,k;

int main() {
    in>>n;
    for(i=2;i*i<=n;i++)
        if(!v[i])
            for(j=2;j*i<=n;j++)
                v[i*j]=1;
    
    for(i=2;i<=n;i++)if(!v[i])k++;
    
    out<<k;
    
    return 0;
}