Does hacker rank evaluate code for speed?

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I am practicing on hacker rank on the following question:

Jesse loves cookies and wants the sweetness of some cookies to be
greater than value . To do this, two cookies with the least sweetness
are repeatedly mixed. This creates a special combined cookie with:

sweetness Least sweet cookie 2nd least sweet cookie).

This occurs until all the cookies have a sweetness .

Given the sweetness of a number of cookies, determine the minimum
number of operations required. If it is not possible, return .


The smallest values are . Remove them then return to the array. Now .
Remove and return to the array. Now . Remove , return and .
Finally, remove and return to . Now . All values are so the process
stops after iterations. Return .

Function Description Complete the cookies function in the editor

cookies has the following parameters:

int k: the threshold value int A[n]: an array of sweetness values

int: the number of iterations required or -1

I wrote this very simple solution in Python:

def cookies(k, A):
    i = 0
    while True:
        if A[0] >= k:
        elif len(A)< 2:
            i = -1
        n1 = A.pop(0)
        n2 = A.pop(0)
        new_cookie = (n1 + 2*n2)
        A.insert(0, new_cookie)
        i += 1
    return i

It fails several test cases. Despite banging my head against the wall and consulting ChatGPT, I don’t see any errors on edge cases. Are there other things (like speed) being evaluated by hacker rank? Is this ‘technically correct’ but not performant/ optimal? Are their crazy edge cases they include like where my sort is causing an overflow?


You can use heapq to solve this problem. Your current approach is inefficient and it fails as commented.

import heapq

def cookies(k, A):
    i = 0

    while len(A) > 1 and A[0] < k:
        n1 = heapq.heappop(A)
        n2 = heapq.heappop(A)
        new_cookie = n1 + 2 * n2
        heapq.heappush(A, new_cookie)
        i += 1

    if A[0] < k:
        return -1
    return i

print(cookies(7, [1, 2, 3, 9, 10, 12]))




  • pop(0) from a list has an O(N) time complexity.
  • insert(0, value) into a list is also O(N) time complexity.