{"id":2376,"date":"2025-03-04T23:27:19","date_gmt":"2025-03-04T14:27:19","guid":{"rendered":"https:\/\/remoooo.com\/?p=2376"},"modified":"2025-03-04T23:27:21","modified_gmt":"2025-03-04T14:27:21","slug":"leetcode4-mar-2025-count-trailing-zeros-in-factorial","status":"publish","type":"post","link":"https:\/\/remoooo.com\/en\/leetcode4-mar-2025-count-trailing-zeros-in-factorial\/","title":{"rendered":"[Leetcode]4 Mar. 2025. Count Trailing Zeros in Factorial"},"content":{"rendered":"

Description:<\/h2>\n\n\n\n

Given an integer $n$ , return the number of trailing zeros in $n!$ (n factorial).<\/p>\n\n\n\n

Factorial is defined as:
$$
n! = n \\times (n \u2013 1) \\times (n \u2013 2) \\times \\dots \\times 3 \\times 2 \\times 1
$$<\/p>\n\n\n\n

Examples:<\/h2>\n\n\n\n

Example 1:
Input: n = 3<\/code>
Output: 0<\/code>
Explanation: 3! = 6<\/code>, which has no trailing zeros.<\/p>\n\n\n\n

Example 2:
Input: n = 5<\/code>
Output: 1<\/code>
Explanation: 5! = 120<\/code>, which has one trailing zero.<\/p>\n\n\n\n

Example 3:
Input: n = 0<\/code>
Output: 0<\/code><\/p>\n\n\n\n

Constraints:<\/h2>\n\n\n\n
    \n
  • $0 \\leq n \\leq 10^4$<\/li>\n<\/ul>\n\n\n\n
    \n\n\n\n
    <\/circle><\/circle><\/circle><\/g><\/svg><\/span><\/path><\/path><\/svg><\/span>
    class<\/span> <\/span>Solution<\/span> {<\/span><\/span>\npublic:<\/span><\/span>\n    <\/span>int<\/span> <\/span>trailingZeroes<\/span>(<\/span>int<\/span> <\/span>n<\/span>) {<\/span><\/span>\n        <\/span>int<\/span> count;<\/span><\/span>\n        <\/span>while<\/span>(n >= <\/span>5<\/span>){<\/span><\/span>\n            n = n \/ <\/span>5<\/span>;<\/span><\/span>\n            count += n;<\/span><\/span>\n        }<\/span><\/span>\n        <\/span>return<\/span> count;<\/span><\/span>\n    }<\/span><\/span>\n};<\/span><\/span>\n<\/span>\n\/*<\/span><\/span>\n## Counting 5 as a factor.<\/span><\/span>\n<\/span>\nWe Need To Determine how many times "10" appears as a factor in the product.<\/span><\/span>\n<\/span>\n10 is formed by multiplying 2 & 5, we can only count 5 as a factor.<\/span><\/span>\n<\/span>\nFor example:<\/span><\/span>\n- 3! = 3*2*1 = 6 -> +0<\/span><\/span>\n- 5! = 5*4*3*2*1 = 120 -> +1<\/span><\/span>\n- 10! = 10*9*...*3*2*1 = 3628800 -> +2<\/span><\/span>\n*\/<\/span><\/span><\/code><\/pre>C++<\/span><\/div>\n\n\n\n
    <\/p>","protected":false},"excerpt":{"rendered":"
    Description: Given an integer $n$ , return the number o […]<\/p>","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-2376","post","type-post","status-publish","format-standard","hentry","category-article"],"_links":{"self":[{"href":"https:\/\/remoooo.com\/en\/wp-json\/wp\/v2\/posts\/2376","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/remoooo.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/remoooo.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/remoooo.com\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/remoooo.com\/en\/wp-json\/wp\/v2\/comments?post=2376"}],"version-history":[{"count":1,"href":"https:\/\/remoooo.com\/en\/wp-json\/wp\/v2\/posts\/2376\/revisions"}],"predecessor-version":[{"id":2377,"href":"https:\/\/remoooo.com\/en\/wp-json\/wp\/v2\/posts\/2376\/revisions\/2377"}],"wp:attachment":[{"href":"https:\/\/remoooo.com\/en\/wp-json\/wp\/v2\/media?parent=2376"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/remoooo.com\/en\/wp-json\/wp\/v2\/categories?post=2376"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/remoooo.com\/en\/wp-json\/wp\/v2\/tags?post=2376"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}