Find Heavier Ball | Dataford Interview Questions

Find the heavier ball from 8 balls.

Assume exactly one ball is heavier than the other seven, and a balance scale is available. Use at most two weighings: first compare balls 0, 1, 2 against balls 3, 4, 5; then compare either balls 0 and 1 or balls 6 and 7, depending on the first result. Each weighing result is 1 if the left side is heavier, -1 if the right side is heavier, and 0 if they balance. Implement find_heavier_ball(first_result, second_result) to return the heavier ball's index from 0 through 7.

Constraints

There are exactly 8 balls indexed from 0 through 7.
Exactly one ball is heavier than the other seven.
first_result and second_result are each one of -1, 0, or 1.
The results are valid outcomes of the described weighing strategy.

Function Signature

def find_heavier_ball(first_result, second_result):

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Problem

Find the heavier ball from 8 balls.

Constraints

There are exactly 8 balls indexed from 0 through 7.
Exactly one ball is heavier than the other seven.
first_result and second_result are each one of -1, 0, or 1.
The results are valid outcomes of the described weighing strategy.

Function Signature

def find_heavier_ball(first_result, second_result):

Your question is Find Heavier Ball. Start with the requirements in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.