Cod sursa(job #660860)

Utilizator roxana_savulescuSavulescu Roxana roxana_savulescu Data 13 ianuarie 2012 14:04:47
Problema Ciurul lui Eratosthenes Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 0.28 kb
Raporteaza aceasta sursa 
#include<fstream>
using namespace std;
long n,i,nr,j;
short a[2000001];
int main(){
	ifstream f("ciur.in");
	ofstream g("ciur.out");
	f>>n;
	for (i=2;i<=n;i++)
		for (j=1;j<=n/i;j++)
			a[j*i]++;
		
	for (i=2;i<=n;i++)
		if (a[i]==1) nr++;
	g<<nr<<"\n";
	return 0;
}