Cod sursa(job #293189)

Utilizator hurrycaneBogdan Gaza hurrycane Data 1 aprilie 2009 00:56:37
Problema Ciurul lui Eratosthenes Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.32 kb
Raporteaza aceasta sursa 
#include<cstdio>
#include<math.h>

unsigned long N;
unsigned long T;
unsigned long i,j;

int s[2000100];

int main(){
	freopen("ciur.in","r",stdin);
	freopen("ciur.out","w",stdout);
	
	scanf("%ld",&N);
	for(i=2;i<=N;i++){
		if(s[i]==0){
			++T;
			for(j=2;j<=N/i;j++){
				s[i*j]=1;
			}
		}
	}
	printf("%ld",T);
	
	return 0;
}