Problem Statement: Unique Paths III LeetCode Solution: You are given an m x n integer array grid where grid[i][j] could be: 1 representing the starting square. There is exactly one starting square. 2 representing the ending square. There is exactly one ending square. 0 representing empty squares we can walk over. -1 representing obstacles that we cannot walk over. Return the …
Problem Statement: Invert Binary Tree LeetCode Solution : Given the root of a binary tree, invert the tree, and return its root. An inverted form of a Binary Tree is another Binary Tree with left and right children of all non-leaf nodes interchanged. You may also call it the mirror of the input tree. …
Problem Statement: Implement strStr() LeetCode Solution – Implement strStr(). Given two strings needle and haystack, return the index of the first occurrence of needle in haystack, or -1 if needle is not part of haystack. Clarification: What should we return when needle is an empty string? This is a great question to ask during an interview. For the purpose of this problem, we …
Problem Statement: Break a Palindrome LeetCode Solution: Given a palindromic string of lowercase English letters palindrome, replace exactly one character with any lowercase English letter so that the resulting string is not a palindrome and that it is the lexicographically smallest one possible. Return the resulting string. If there is no way to replace a character to make …
Problem Statement: Contains Duplicate LeetCode Solution says that- Given an integer array nums, return true if any value appears at least twice in the array, and return false if every element is distinct. Example 1: Input: nums = [1,2,3,1] Output: true Example 2: Input: nums = [1,2,3,4] Output: false Example 3: Input: nums = [1,1,1,3,3,4,3,2,4,2] Output: …
Problem Statement: Best Time to Buy and Sell Stock IV LeetCode Solution: You are given an integer array prices where prices[i] is the price of a given stock on the ith day, and an integer k. Find the maximum profit you can achieve. You may complete at most k transactions. Note: You may not engage in multiple transactions simultaneously …
Problem Statement: Find First and Last Position of Element in Sorted Array LeetCode Solution says that – given an array of integers nums sorted in non-decreasing order, find the starting and ending position of a given target value. If target is not found in the array, return [-1, -1]. You must write an algorithm with O(log n) runtime complexity. …
Problem Statement: Lowest Common Ancestor of a Binary Search Tree Leetcode Solution – Given a binary search tree (BST), find the lowest common ancestor (LCA) node of two given nodes in the BST. Note: “The lowest common ancestor is defined between two nodes p and q as the lowest node in T that has both p and q as …
Problem Statement Find Peak Element LeetCode Solution says that – A peak element is an element that is strictly greater than its neighbors. Given a 0-indexed integer array nums, find a peak element, and return its index. If the array contains multiple peaks, return the index to any of the peaks. You may imagine …
Problem Statement Valid Anagram Leetcode Solution – Given two strings s and t, return true if t is an anagram of s, and false otherwise. An Anagram is a word or phrase formed by rearranging the letters of a different word or phrase, typically using all the original letters exactly once. Example 1: Input: s = “anagram”, t = “nagaram” Output: …