Cod sursa(job #1734832)

Utilizator patcasrarespatcas rares danut patcasrares Data 28 iulie 2016 13:17:54
Problema Ciurul lui Eratosthenes Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 0.29 kb
Raporteaza aceasta sursa 
#include<fstream>
using namespace std;
ifstream fin("ciur.in");
ofstream fout("ciur.out");

int main()
{
long long n,i,j,nr=1;
fin>>n;
int a[200000];
for(i=1;i<=n;i++)
    a[i]=0;
for(i=3;i<=n;i=i+2)
if(!a[i]){nr++;
    for(j=i+i+i;j<=n;j=j+2*i)
    a[j]=1;}
    fout<<nr;
}