Given an integer `n`

represented as a string, return *the smallest good base of*

`n`

.We call `k >= 2`

a **good base** of `n`

, if all digits of `n`

base `k`

are `1`

's.

**Example 1:**

Input:n = "13"Output:"3"Explanation:13 base 3 is 111.

**Example 2:**

Input:n = "4681"Output:"8"Explanation:4681 base 8 is 11111.

**Example 3:**

Input:n = "1000000000000000000"Output:"999999999999999999"Explanation:1000000000000000000 base 999999999999999999 is 11.

**Constraints:**

`n`

is an integer in the range`[3, 10`

.^{18}]`n`

does not contain any leading zeros.

public class Solution {
public string SmallestGoodBase(string n) {
}
}