Identify Heavier Ball

MediumPython

Problem

Suppose we have 8 balls with identical weight and a heavier one. How many times do you need to use the scale to identify the heavier ball?

Implement minimum_weighings(num_balls) for num_balls identical balls containing exactly one heavier ball. Each balance-scale use compares two groups and has three possible outcomes: left heavier, right heavier, or balanced. Return the minimum worst-case number of weighings needed to guarantee identification.

Constraints

1 <= num_balls <= 10^18
Exactly one ball is heavier than all others
The scale is a balance scale with three possible outcomes

Function Signature

def minimum_weighings(num_balls):

CodePython 3

You need to log in / sign up to run or submit.Ln 2

Run your code to see test output here.