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Python Python Collections (2016, retired 2019) Dictionaries Packing and Unpacking Dictionaries

Posted by Vishal Vikram
Vishal Vikram
251 Points

Your task is to construct a building which will be a pile of n cubes. The cube at the bottom will have a volume of n^3,

Your task is to construct a building which will be a pile of n cubes. The cube at the bottom will have a volume of n^3, the cube above will have volume of (n-1)^3 and so on until the top which will have a volume of 1^3.

You are given the total volume m of the building. Being given m can you find the number n of cubes you will have to build?

The parameter of the function findNb (find_nb, find-nb) will be an integer m and you have to return the integer n such as n^3 + (n-1)^3 + ... + 1^3 = m if such a n exists or -1 if there is no such n.

1 Answer

James J. McCombie
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.a{fill-rule:evenodd;}techdegree seal-36
James J. McCombie
Python Web Development Techdegree Graduate 21,199 Points
James J. McCombie
.a{fill-rule:evenodd;}techdegree seal-36
James J. McCombie
Python Web Development Techdegree Graduate 21,199 Points

Hello,

Not entirely sure why you have posted this, for help?, stuck on a challenge?

well this will get the result you want...

def findNB(m):
    if 1 ** 3 == m:
        return 1
    else:
        n = 2
        volume = 1
        while volume < m:
            volume = volume + n ** 3
            if volume == m:
                return n
            else:
                n = n + 1
                continue
        return -1

could probably make this more elegant, perhaps solve recursively, but that's just a quick stab at it, if you could give a little more information around what you want from this question, perhaps I can assist better. I have tested this function, it works fine.