Cod sursa(job #663590)

Utilizator Bogdy4FuNBogdan Ciubotaru Bogdy4FuN Data 18 ianuarie 2012 18:54:01
Problema Ciurul lui Eratosthenes Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 0.31 kb
Raporteaza aceasta sursa 
#include<fstream>
using namespace std;

ifstream f("ciur.in");
ofstream g("ciur.out");

int ciur[2000000];

int main ()
{
	int i,j,n,nr=0;
	f>>n;
	for (i=2;i*i<=n;i++)
		if(ciur[i]!=1)
			for (j=2;i*j<=n;j++)
				ciur[i*j]=1;
	for (i=2;i<=n;i++)
		if(ciur[i]==0)
			nr++;
	g<<nr;
	return 0;
}