Cod sursa(job #837700)

Utilizator alexandru213Bracau Alexandru alexandru213 Data 18 decembrie 2012 15:18:21
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.27 kb
#include <fstream>
using namespace std;
ifstream in("ciur.in");
ofstream out("ciur.out");
char a[2000001];
int n,j,nr,i;
int main () {
	in>>n;nr=0;
	for(i=2;i<=n;i++)
		if(a[i]==0){
			nr++;
			for(j=2*i;j<=n;j=j+i)
		    	a[j]=1;
		}
	out<<nr;
	return 0;}