Cod sursa(job #709987)

Utilizator vlad.tudorVlad Tudor vlad.tudor Data 8 martie 2012 19:10:55
Problema Ciurul lui Eratosthenes Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 0.29 kb
#include <fstream>
using namespace std;
int a[2000000];
int main()
{
	ifstream f("ciur.in");
	int n,i,o,rez;
	f>>n;
	rez=0;
	f.close();
	for(i=2;i<=n;i++)
	{
		if(a[i]==0)
			rez++;
	for(o=i;o<=n;o+=i)
		a[o]=1;
	}
ofstream g("ciur.out");
g<<rez;
g.close();
return 0;
}