Cod sursa(job #664546)

Utilizator loredanacosteaCostea Loredana loredanacostea Data 20 ianuarie 2012 12:19:21
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,i,j,nr;
char a[2000001] ;

int main()
{
	ifstream f("ciur.in");
	ofstream g("ciur.out");
	f>>n;
	for(i=2;i<=n;i++)
	{
		if(a[i]==0)
		{
			nr++;
			for(j=i+i;j<=n;j+=i)
				a[j]=1;
		}
	}
	g<<nr;
	return 0;
}