How hard is LeetCode 2390. Removing Stars From a String?

LeetCode 2390. Removing Stars From a String is rated Medium on LeetCode.

What is the time complexity of LeetCode 2390. Removing Stars From a String?

The Python solution on this page runs in O(n), where n is the length of the string s.

What is the space complexity of LeetCode 2390. Removing Stars From a String?

The Python solution on this page uses O(1) auxiliary space.

What topics does LeetCode 2390. Removing Stars From a String cover?

LeetCode 2390. Removing Stars From a String is tagged Stack, String and Simulation on LeetCode.

Removing Stars From a String — LeetCode 2390 Python Solution

MediumStackStringSimulation

Problem: #2390
Pattern: Stack
Reading time: 2 min
Source: leetcode.com

The problem

You are given a string s, which contains stars *. In one operation, you can: Choose a star in s.

Example

Input: s = "leet**cod*e"
Output: "lecoe"
Explanation: Performing the removals from left to right:

Python solution

Python

class Solution:
    def removeStars(self, s: str) -> str:
        ans = []
        for c in s:
            if c == '*':
                ans.pop()
            else:
                ans.append(c)
        return ''.join(ans)

Complexity

Measure	Complexity
Time	O(n), where n is the length of the string s
Space	O(1) auxiliary

Pattern: Stack

When the most recent unresolved thing is the one that matters, use a stack. LeetCode 2390. Removing Stars From a String is filed here on both counts: the reference solution below belongs to the algorithm family this hub collects, and LeetCode tags it Stack.

The stack guide has the Python template for the pattern and the 194 LeetCode problems that use it.

On a study list

This problem is on LeetCode 75.

Frequently asked questions

How hard is LeetCode 2390. Removing Stars From a String?: LeetCode 2390. Removing Stars From a String is rated Medium on LeetCode.
What is the time complexity of LeetCode 2390. Removing Stars From a String?: The Python solution on this page runs in O(n), where n is the length of the string s.
What is the space complexity of LeetCode 2390. Removing Stars From a String?: The Python solution on this page uses O(1) auxiliary space.
What topics does LeetCode 2390. Removing Stars From a String cover?: LeetCode 2390. Removing Stars From a String is tagged Stack, String and Simulation on LeetCode.