Cod sursa(job #386203)

Utilizator andrei.finaruFinaru Andrei Emanuel andrei.finaru Data 24 ianuarie 2010 12:39:35
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.3 kb
#include<fstream>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
int c,n,i,j;
char prim[2000001];
int main()
{
	f>>n;
	for(i=2;i<=n;i++)
		prim[i]=1;
	for(i=2;i<=n;i++)
		if(prim[i])
		{for(j=i;j<=n;j=j+i)
			prim[j]=0;
		c++;}
	g<<c;
	f.close(); g.close();
	return 0;
}