Given a set of candidate numbers (candidates) (without duplicates) and a target number (target), find all unique combinations in candidates where the ...

Given a binary tree, return the bottom-up level order traversal of its nodes’ values. (ie, from left to right, level by level from leaf to root). Exam ...

Given a binary tree, return the level order traversal of its nodes’ values. (ie, from left to right, level by level). ExampleGiven binary tree [3,9,20 ...

Given a binary tree, return the postorder traversal of its nodes’ values. ExampleInput: [1,null,2,3] 123451 \ 2 /3 Output: [3,2,1] Follow upRecursiv ...

Given a binary tree, return the inorder traversal of its nodes’ values. ExampleInput: [1,null,2,3] 123451 \ 2 /3 Output: [1,3,2] Follow upRecursive ...

Given a binary tree, return the preorder traversal of its nodes’ values. ExampleInput: [1,null,2,3] 123451 \ 2 /3 Output: [1,2,3] Follow upRecursive ...

Reverse a linked list from position m to n. Do it in one-pass. Note1 ≤ m ≤ n ≤ length of list. ExampleInput: 1->2->3->4->5->NULL, m = 2 ...

Reverse a singly linked list. ExampleInput: 1->2->3->4->5->NULL Output: 5->4->3->2->1->NULL Follow upA linked list can b ...

Given a linked list, return the node where the cycle begins. If there is no cycle, return null. To represent a cycle in the given linked list, we use ...

Given a linked list, determine if it has a cycle in it. To represent a cycle in the given linked list, we use an integer pos which represents the posi ...