Embedly Challenge

embedly.py

"""These are my answers for the Embedly Challenge""" 

from xml.etree import ElementTree
from numpy import std # you'll need numpy for Question 2

def question1():
    def digitSum(x):
        # pretty ugly, eh?
        return sum(map(int, list(str(x))))
    
    f, i = 1, 1
    while digitSum(f) < 8001:
        f, i = f * i, i + 1
    return i - 1

def question2():
    l = []

    def recurNode(node, level):
        if node != None:
            if node.tag == "p":
               l.append(level)
            for item in node.getchildren():
                recurNode(item, level + 1)
        else:
            return 0

    # here I got lazy: did not fetch the html directly from the website and I
    # removed everything (e.g., body tag) except the article tag to make 
    # things easier
    recurNode(ElementTree.parse("2.html").getroot(), 0)
    return std(l) # std from numpy
    
def question3():
    # a simple bruteforce solution
    l = [2520]
    for i in range (1,900):
        l.append(l[0] / (i + 1))
    total, half, i = sum(l), 0, 0
    while half < (total / 2):
        half, i = half + l[i], i + 1
    return i

if __name__ == "__main__":
    print(question1())
    print(question2())
    print(question3())

I just tried your question3 on my computer and it returns 21!

I'm pretty sure the answer is 22!

@yassersouri Yes, it's 22 and that's what I get. Can you give me more details about your machine (Python version, 32/64 bit, OS)? Let me know if you discover the issue.

I'm running python 2.7 on windows 7, 32 bit

I don't think It's a machine dependency issue.

I just tried to implement your solution using Java and got the same (21) output:

public class Problem3 {
    public static void main(String[] args) {
        int[] l = new int[900];
        l[0] = 2520;
        for (int i = 1; i < l.length; i++) {
            l[i] = l[0] / (i + 1);
        }

        int total = 0;
        for (int i = 0; i < l.length; i++) {
            total += l[i];
        }

        int half = 0;
        int i = 0;
        while (half < total/2) {
            half = half + l[i];
            i++;
        }
        System.out.println(i);
    }
}

BTW I have no idea why this code does not generate the required output. It seems to be ok.

@yassersouri It's a rounding issue; try using float/double instead of int in your Java code.