Cod sursa(job #504845)

Utilizator Dumitru_GeorgeDumitru George Cristian Dumitru_George Data 28 noiembrie 2010 23:24:42
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.33 kb
Raporteaza aceasta sursa 
#include<iostream>
#include<fstream>
#define N 2000001
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
long long i,j,n,t;
char v[N];
int main()
{
f>>n;
for(i=2;i*i<=n;i++)
	if(v[i]==0)
		for(j=i;i*j<=n;j++)v[i*j]=1;
for(i=2;i<=n;i++)
	if(v[i]==0)t++;
g<<t;
	f.close();
	g.close();
	return 0;
}