Problem
Given an integer n, return the number of trailing zeroes in n!.
Example 1:
Input: 3
Output: 0
Explanation: 3! = 6, no trailing zero.
Example 2:
Input: 5
Output: 1
Explanation: 5! = 120, one trailing zero.
**Note: **Your solution should be in logarithmic time complexity.
Solution
/**
* @param {number} n
* @return {number}
*/
var trailingZeroes = function(n) {
if (n === 0) return 0;
return Math.floor(n / 5) + trailingZeroes(Math.floor(n / 5));
};
Explain:
nope.
Complexity:
- Time complexity : O(log(n)).
- Space complexity : O(1).