Is Remove Vowels from a String easy or hard?

Remove Vowels from a String is classified as an Easy problem. It focuses on basic string traversal and filtering without requiring advanced data structures or algorithms.

Remove Vowels from a String Python/Java solution

In Python, iterate through the string and append non-vowel characters to a list, then join them into a string. In Java, loop through the characters and append valid ones to a StringBuilder. Both implementations follow the same O(n) simulation pattern.

How to solve Remove Vowels from a String in O(n)?

Iterate through the string from left to right and check whether each character is a vowel. Maintain a set like "aeiou" for constant-time membership checks. Append only the characters that are not vowels to a result builder, then join them into the final string. The single traversal guarantees O(n) time complexity.

What is the best approach for Remove Vowels from a String?

The optimal approach is a single-pass simulation that scans the string and skips characters that are vowels. Store vowels in a set such as {a, e, i, o, u} for constant-time checks. Append only non-vowel characters to the result. This runs in O(n) time and O(n) space.

Is Remove Vowels from a String asked at Google/Amazon/Meta?

Problems involving string filtering and character processing frequently appear in interviews at companies like Amazon, Google, and Meta. While this exact problem is simple, it tests core skills such as iteration, conditional checks, and efficient string construction.

What data structure is used in Remove Vowels from a String?

A hash set or constant lookup structure is typically used to store vowels for O(1) membership checks. The result is built using a list, string builder, or dynamic character buffer before converting it back into a string.

What is the time complexity of Remove Vowels from a String?

The standard solution runs in O(n) time where n is the length of the string. Each character is visited exactly once and checked against a vowel set with O(1) lookup. Space complexity is O(n) because a new string is created to store the filtered characters.

Description Hints 2 Solution Video 5:43

1119. Remove Vowels from a String

Easy91.2% acceptance1 companyPremium elsewhere, free here

Given a string s, remove the vowels 'a', 'e', 'i', 'o', and 'u' from it, and return the new string.

Example 1:

Input: s = "leetcodeisacommunityforcoders"
Output: "ltcdscmmntyfrcdrs"

Example 2:

Input: s = "aeiou"
Output: ""

Constraints:

1 <= s.length <= 1000
s consists of only lowercase English letters.

Asked at 1 company

Amazon

Topics

String

Hints open one at a time

Hint 1

How to erase vowels in a string?

Hint 2

Loop over the string and check every character, if it is a vowel ignore it otherwise add it to the answer.

5:43

Still stuck?Read the written solution, or watch a walkthrough.

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