Given an integer n, return the number of trailing zeroes in n!. Follow up: Could you write a solution that works in logarithmic time complexity? Example 1: Input: n = 3 Output: 0 Explanation: 3! = 6, no trailing zero. Example 2: Input: n = 5 Output: 1 Explanation: 5! = 120, one trailing zero. Example 3: Input: n = 0 Output: 0 Constraints: 0 <= n <= 104