Cod sursa(job #1693922)

Utilizator bassista02Dorela Marina bassista02 Data 24 aprilie 2016 11:21:32
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;
int n,m,a[2000001];
ifstream fin("ciur.in");
ofstream fout("ciur.out");
int main(){
fin>>n;m=n;
for(int i=2;i<=n;i++)a[i]=i;
for(int i=2;i*i<=n;i++)
    if(a[i]) for(int j=i+i;j<=n;j=j+i) if(a[j]){a[j]=0;m--;}
fout<<m-1<<'\n';
return 0;

}