Cod sursa(job #709994)

Utilizator vlad.tudorVlad Tudor vlad.tudor Data 8 martie 2012 19:14:12
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.3 kb
#include <fstream>
using namespace std;
char a[2000001];
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;
}