Cod sursa(job #1693923)

Utilizator bassista02Dorela Marina bassista02 Data 24 aprilie 2016 11:33:55
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.27 kb
Raporteaza aceasta sursa 
#include<fstream>
using namespace std;
int n,m;
bool a[2000001];
ifstream fin("ciur.in");
ofstream fout("ciur.out");
int main(){
fin>>n;m=n;

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]=1;m--;}
fout<<m-1<<'\n';
return 0;

}