Cod sursa(job #700435)

Utilizator mads2194FMI - Andrei Stroe mads2194 Data 1 martie 2012 10:20:23
Problema Ciurul lui Eratosthenes Scor 20
Compilator cpp Status done
Runda Arhiva educationala Marime 0.33 kb
Raporteaza aceasta sursa 
#include<iostream>
#include<fstream>

using namespace std;

bool c[2000001];

int main()
{
	fstream fin("ciur.in",ios::in);
	fstream fout("ciur.out",ios::out);
	short int n,s=0;
	fin>>n;
	for (short int i=2;i<=n;i++)
		if(! c[i])
		{
			s++;
			for(short int j=i;j<=n;j+=i)
				c[j]=1;
		}
	fout<<s;
	return 0;
}