Cod sursa(job #1889696)

Utilizator cameleonGeorgescu Dan cameleon Data 22 februarie 2017 20:47:28
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.29 kb
Raporteaza aceasta sursa 
#include <fstream>
using namespace std;
 
ifstream f("ciur.in");
ofstream g("ciur.out");
char a[2000001];
int n,i,j,nr;
int main()
{
f>>n;nr=0;
for (i=2;i<=n;i++)
{   if (a[i]==0)
    {nr++;
    for (j=i;j<=n/i;j++)
        a[i*j]=1; 
    }
}
g<<nr;
g.close();
return 0;
}