Cod sursa(job #558613)

Utilizator puya.tudorPuia Tudor puya.tudor Data 17 martie 2011 13:04:06
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.31 kb
Raporteaza aceasta sursa 
#include<fstream>
using namespace std;

char x[2000001];
int main()
{
	int n,i,j,c=0;;
	ifstream In("ciur.in");
	In>>n;
	In.close();
	
	for(i=2;i<n;i++)
	{
		if(!x[i])
		{
		   for(j=2*i;j<=n;j+=i)
		      x[j]=1;
		   c++;
		}
	}
	
	ofstream Out("ciur.out");
	Out<<c;
	Out.close();
	return 0;
}