May 23, 2019
Given a string, your task is to count how many palindromic substrings in this string. The substrings with different start indexes or end indexes are counted as different substrings even they consist of same characters.
May 19, 2019
Given a sorted array nums, remove the duplicates in-place such that each element appear only once and return the new length. Do not allocate extra space for another array, you must do this by modifying the input array in-place with O(1) extra memory.
May 18, 2019
Given a binary tree, find the lowest common ancestor (LCA) of two given nodes in the tree. 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 descendants.
May 16, 2019
The function first discards as many whitespace characters as necessary until the first non-whitespace character is found. Then, starting from this character, takes an optional initial plus or minus sign followed by as many numerical digits as possible, and interprets them as a numerical value.
May 13, 2019
A heap is a tree-based data structure which satisfies the heap property, if the parent node is greater than the child node is called max-heap or if the parent node is less than the child node is called min-heap.