Reverse String - Write a function that reverses a string. The input string is given as an array of characters s. You must do this by modifying the input array in-place [https://en.wikipedia.org/wiki/In-place_algorithm] with O(1) extra memory.

So, we solved the reverse string problem by using two pointer method and calculated the time and space complexities.

November 27, 2023 - In this article, we will explore the LeetCode problem “Reverse String” and provide a JavaScript solution to reverse an array of characters in place. The challenge here is to modify the input array in situ, without using additional memory (O(1) extra memory).

October 18, 2021 - I’m not sure why the question is posed as a string reversal when the input is already an array but here we go… · This is my solution, which has a runtime of 199ms (beats 9.95% of JS solutions) and memory usage of 46.1MB (beats 67% of JS solutions). I toyed with having a variable halfLength for the loop, which sometimes lowered memory usage significantly but also increased runtime. I get different numbers every time I submit a LeetCode solution so it’s basically a toss up and I went with a cleaner version without the variable.

March 22, 2021 - var reverseStr = function(s, k) { // strings are immutable in javascript // converting to an array will allow in place letter swapping const a = s.split(''); // loop through the array in 2*k increments for (let start = 0; start < a.length; start ...

December 24, 2024 - Reversing the words in a string while handling multiple spaces efficiently is a common problem in string manipulation. Let's tackle LeetCode 151: Reverse Words in a String with an optimized solution and without using predefined methods like split or trim.

October 18, 2020 - var reverseString = function(s) { for (let i = 0; i < s.length/2; i++) { let n = s[i] s[i] = s[s.length-i-1] s[s.length-i-1] = n } }; This solution will use a for loop to iterate the string all the way to the middle and swap the left side character ...

The approach is as follows · We declare an array of vowels and assign all the uppercase and lowercase vowels to it · Next, we convert the string to an array and apply two pointer approach to reverse the vowels

Can you solve this real interview question? Reverse Words in a String - Given an input string s, reverse the order of the words. A word is defined as a sequence of non-space characters.

Reverse String II - Given a string s and an integer k, reverse the first k characters for every 2k characters counting from the start of the string. If there are fewer than k characters left, reverse all of them.

/** * @param {character[]} s * @return {void} Do not return anything, modify s in-place instead. */ var reverseString = function (s) { let left = 0; let right = s.length - 1; while (left < right) { char = s[left]; s[left] = s[right]; s[right] = char; left++; right--; } };

January 31, 2024 - class Solution { public String reverseStr(String s, int k) { char[] arr = s.toCharArray(); for (int i = 0; i < arr.length; i += 2 * k) { int left = i; int right = i + k - 1; if (right >= arr.length) { right = arr.length - 1; } while (left < right) { char temp = arr[left]; arr[left] = arr[right]; arr[right] = temp; left++; right--; } } return new String(arr); } } Leetcode · String · Java · JavaScript ·

Reverse Vowels of a String - Given a string s, reverse only all the vowels in the string and return it. The vowels are 'a', 'e', 'i', 'o', and 'u', and they can appear in both lower and upper cases, more than once.

The optimal way to reverse a string in-place is by using the two-pointer technique.

Then we loop through the string we receive using an ES6 for...of loop (see the docs) and pushing each character to the reversed string. So if we had hello then we would loop through and add h to a blank string. Then our next character is e which would be added to our string which has now become eh. Run in sequence you get: ... This is pretty straighforward and has a time complexity of O(n). Reduce is a Javascript array method which is really useful.

Can you solve this real interview question? Reverse Words in a String II - Level up your coding skills and quickly land a job. This is the best place to expand your knowledge and get prepared for your next interview.