Cod sursa(job #2471172)

Utilizator alexmorosanuMorosanu Alexandru alexmorosanu Data 10 octombrie 2019 15:35:08
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.3 kb
#include<fstream>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");

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