Cod sursa(job #690420)

Utilizator FernandoSandoiu Fernando Fernando Data 25 februarie 2012 16:44:07
Problema Ciurul lui Eratosthenes Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 0.34 kb
Raporteaza aceasta sursa 
#include<fstream>
using namespace std;
int main()
{long n,i,j,p;
int e[2000001];
ifstream f("ciur.in");
ofstream g("ciur.out");
f>>n;
e[1]=1;
for(i=2;i<=n;i++)
	e[i]=0;
for(i=2;i<=n;i++)
   if(e[i]==0)
	   for(j=i+i;j<=n;j+=i)
		   e[j]=1;
p=0;
for(i=1;i<=n;i++)
	if(e[i]==0)
		p++;
g<<p;
f.close();
g.close();
return 0;}