LeetCode 2710. Remove Trailing Zeros From a String

Given a positive integer num represented as a string, return the integer num without trailing zeros as a string.

Example 1:

Input: num = "51230100"Output: "512301"Explanation: Integer "51230100" has 2 trailing zeros, we remove them and return integer "512301".

Example 2:

Input: num = "123"Output: "123"Explanation: Integer "123" has no trailing zeros, we return integer "123".

Constraints:

• 1 <= num.length <= 1000

• num consists of only digits.

• num doesn't have any leading zeros.

使用stringbuilder的方法，因为stringbuilder有reverse的函数。

Runtime: 5 ms, faster than 50.00% of Java online submissions for Remove Trailing Zeros From a String.

Memory Usage: 44.4 MB, less than 12.50% of Java online submissions for Remove Trailing Zeros From a String.