Cod sursa(job #550180)

Utilizator AlikingAlin Mogis Aliking Data 9 martie 2011 12:01:00
Problema Ciurul lui Eratosthenes Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 0.28 kb
#include<fstream.h>
#include<math.h>
int main()
{
	ifstream fin("ciur.in");
	ofstream fout("ciur.out");
	long long n,i,d,s=1,p,x;
	fin>>n;
	for(i=3;i<=n;i++)
	{
		x=sqrt(i);
		p=0;
		for(d=2;d<=x&&p==0;d++)
			if(i%d==0)	p++;
		if(p==0) s++;
	}
	fout<<s;
	return 0;
}