File: number-of-steps-to-reduce-a-number-to-zero/solution.py

Date: 2026-06-06

Time: 18:21

number-of-steps-to-reduce-a-number-to-zero/solution.py

Purpose

This file implements LeetCode 1342: Number of Steps to Reduce a Number to Zero. It owns a single responsibility: given a non-negative integer, count how many steps it takes to reach zero by repeatedly halving (if even) or subtracting one (if odd).

Key Components

Solution class — Container following LeetCode's expected interface.

queensAttacktheKing(self, num: int) -> int — The core implementation. Despite the name (which belongs to LeetCode 1222, an entirely different problem about chess queens), this method implements the reduce-to-zero algorithm. The docstring is correct even though the method name is wrong.

numberOfSteps — A class-level alias (line 17) that binds the correct LeetCode method name to the misnamed implementation. This is what test files call. It's assigned as a bare attribute, not a @property or wrapper — it's just another name for the same unbound function object.

Patterns

Dependencies

Imports: None. The file is entirely self-contained — no stdlib, no third-party, no project-internal imports.

Imported by: The "Imported By" list shows ~400+ test files across the repo referencing this module. That massive fan-in is a repo-level artifact — those test files are almost certainly importing their *own* local solution.py via a relative or path-based import pattern, and the static analysis tool flagged them all as importing from this one. The real consumer is number-of-steps-to-reduce-a-number-to-zero/test_solution.py.

Flow

1. Initialize steps = 0.

2. Loop while num > 0:

3. Return steps.

This is a direct simulation — no closed-form math, no bit tricks. For num = 14: 14→7→6→3→2→1→0 = 6 steps.

Invariants

Error Handling

None. No input validation, no exceptions raised, no edge-case guards. The code trusts the caller to provide a non-negative integer per the LeetCode contract. Passing a float, negative, or non-numeric value would either produce wrong results or raise a TypeError from the modulo/division operators.