Abhishek Sharma

Question Given the roots of two binary trees p and q, write a function to check if they are the same or not. Two binary trees are considered the same if they are structurally identical, and the nodes have the same value. Example 1: Input: p = [1,2,3], q = [1,2,3] Output: true Example 2: Input: p = […]

Question Given the root of a binary tree, determine if it is a valid binary search tree (BST). A valid BST is defined as follows: The left subtree of a node contains only nodes with keys less than the node’s key. The right subtree of a node contains only nodes with keys greater than the node’s key. Both the left and right subtrees must

Question Given the root of a binary tree, return the inorder traversal of its nodes’ values. Example 1: Input: root = [1,null,2,3] Output: [1,3,2] Example 2: Input: root = [] Output: [] Example 3: Input: root = [1] Output: [1] Constraints: The number of nodes in the tree is in the range [0, 100]. -100 <= Node.val <= 100

Question Given the head of a singly linked list and two integers left and right where left <= right, reverse the nodes of the list from position left to position right, and return the reversed list. Example 1: Input: head = [1,2,3,4,5], left = 2, right = 4 Output: [1,4,3,2,5] Example 2: Input: head = [5], left = 1, right = 1 Output: [5] Constraints: The

Question You are given two integer arrays nums1 and nums2, sorted in non-decreasing order, and two integers m and n, representing the number of elements in nums1 and nums2 respectively. Merge nums1 and nums2 into a single array sorted in non-decreasing order. The final sorted array should not be returned by the function, but instead be stored inside the array nums1. To accommodate this, nums1 has a length of m + n, where the first m elements denote

Question Given the head of a linked list and a value x, partition it such that all nodes less than x come before nodes greater than or equal to x. You should preserve the original relative order of the nodes in each of the two partitions. Example 1: Input: head = [1,4,3,2,5,2], x = 3 Output: [1,2,2,4,3,5] Example 2: Input: head = [2,1], x = 2

Question Given a rows x cols binary matrix filled with 0‘s and 1‘s, find the largest rectangle containing only 1‘s and return its area. Example 1: Input: matrix = [[“1″,”0″,”1″,”0″,”0”],[“1″,”0″,”1″,”1″,”1”],[“1″,”1″,”1″,”1″,”1”],[“1″,”0″,”0″,”1″,”0”]] Output: 6 Explanation: The maximal rectangle is shown in the above picture. Example 2: Input: matrix = [[“0”]] Output: 0 Example 3: Input: matrix = [[“1”]] Output: 1 Constraints: rows == matrix.length cols

Question Given an array of integers heights representing the histogram’s bar height where the width of each bar is 1, return the area of the largest rectangle in the histogram. Example 1: Input: heights = [2,1,5,6,2,3] Output: 10 Explanation: The above is a histogram where width of each bar is 1. The largest rectangle is shown in the red

Question Given the head of a sorted linked list, delete all duplicates such that each element appears only once. Return the linked list sorted as well. Example 1: Input: head = [1,1,2] Output: [1,2] Example 2: Input: head = [1,1,2,3,3] Output: [1,2,3] Constraints: The number of nodes in the list is in the range [0, 300]. -100 <= Node.val <= 100 The

Question Given the head of a sorted linked list, delete all nodes that have duplicate numbers, leaving only distinct numbers from the original list. Return the linked list sorted as well. Example 1: Input: head = [1,2,3,3,4,4,5] Output: [1,2,5] Example 2: Input: head = [1,1,1,2,3] Output: [2,3] Constraints: The number of nodes in the list is in the range [0, 300]. -100