Cod sursa(job #446434)

Utilizator voikybodea voichita voiky Data 25 aprilie 2010 21:01:56
Problema Ciurul lui Eratosthenes Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 0.29 kb
Raporteaza aceasta sursa 
#include<fstream.h>

int n,k,ciur[2000001];

int main()
{
	ifstream f("ciur.in");ofstream g("ciur.out");
	int i=2,j;
	f>>n;
	while(i<=n)
	{
		ciur[i]=1;
		k++;
		j=i;
		while(j<=n-i){j+=i;ciur[j]=2;}
		while(i<=n && ciur[i])i++;
	}
	g<<k;
	f.close();g.close();
	return 0;
}