Introduction Link to heading
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 Link to heading
Golang:
func trailingZeroes(n int) int {
zeros := 0
for i := 5; n / i >= 1; i *= 5 {
zeros += n / i
}
return zeros
}
Explanation Link to heading
We need to calculate divisions on 5, 5^2, 5^3, and so on, because we 0 comes from 2*5, and we have a lot of 2s.