import datetime
import math

dt=datetime.datetime.now()

def GeneratePrimes (Limit):
    candidates = []
    primes = [2,3]
    i = 1

    while  6*i+1 < Limit:
        candidates.append( 6*i-1)
        candidates.append( 6*i+1)
        i += 1

    for i in range(0,len(candidates)):
        is_prime = True
        current_max = math.floor(math.sqrt(candidates[i])+1)

        j = 0
        while  candidates[j]< current_max:
            if candidates[i]%candidates[j] == 0:
                is_prime = False
                break
            j += 1

        if(is_prime):
            primes.append(candidates[i])

    return primes

primes = GeneratePrimes(1000000)

dt1 = datetime.datetime.now()

print len(primes)
print dt1 - dt

dt = new Date();

function GeneratePrimes(Limit)
{
    var candidates = [];
    var primes = [2,3];
    var i = 1;

    while(6*i+1 < Limit)
    {
        candidates.push( 6*i-1);
        candidates.push( 6*i+1);
        i += 1;
    }

    for( i=0; i<candidates.length; i++)
    {
        var is_prime = true;
        var current_max = Math.floor(Math.sqrt(candidates[i])+1);

        var j = 0;
        while( candidates[j] < current_max)
	{
            if( candidates[i]%candidates[j] == 0 )
	    {
                is_prime = false;
                break;
	    }

            j += 1;
	}

        if(is_prime)
	{
            primes.push(candidates[i]);
	}
    }

    return primes;
}

primes = GeneratePrimes(1000000);

var dt1 = new Date();

console.log(primes.length);
console.log( dt1.getTime() - dt.getTime());