Remove Trailing Zeros From a String — LeetCode 2710 Python Solution

EasyString
Problem
#2710
Pattern
Hash Map
Reading time
2 min

The problem

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

Example

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

Python solution

Python
class Solution:
    def removeTrailingZeros(self, num: str) -> str:
        return num.rstrip("0")

Complexity

MeasureComplexity
TimeO(n), where n is the length of the string
SpaceO(1) auxiliary

Pattern: Hash Map

Trade memory for time: remember what you have seen so the second pass never happens. LeetCode 2710. Remove Trailing Zeros From a String is filed here because the reference solution below belongs to the algorithm family this hub collects, even though its LeetCode tags point elsewhere.

The hash map guide has the Python template for the pattern and the 709 LeetCode problems that use it.

Related problems

Frequently asked questions

How hard is LeetCode 2710. Remove Trailing Zeros From a String?
LeetCode 2710. Remove Trailing Zeros From a String is rated Easy on LeetCode.
What is the time complexity of LeetCode 2710. Remove Trailing Zeros From a String?
The Python solution on this page runs in O(n), where n is the length of the string.
What is the space complexity of LeetCode 2710. Remove Trailing Zeros From a String?
The Python solution on this page uses O(1) auxiliary space.
What topics does LeetCode 2710. Remove Trailing Zeros From a String cover?
LeetCode 2710. Remove Trailing Zeros From a String is tagged String on LeetCode.

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