Code Room
CodingMediumcod-g173
Subject Modular arithmeticLevel Mid–Senior~18 minCommon in Algorithms & data structures interviewsIndustries Software development

Question

Given a non-negative integer n (up to 10^9), return the number of trailing zeros in n! (n factorial). For example 5! = 120 has one trailing zero. You must not compute n! directly — it is astronomically large.

Implement
trailing_zeros_factorial(n: int) → int
Examples
in[5]out1
What a strong answer looks like

State your approach and its time/space complexity out loud before you optimize. Handle the edge cases (empty input, duplicates, overflow), and say why you chose this over the brute force. Green tests are the floor, not the grade.

Vibe coding: describe the solution in plain language (or narrate it) and the coach grades your approach. Generating runnable code from your description is coming next.

Run or narrate your approach, then ask the coach.