Remove all elements from a linked list of integers that have value val. Example*****Given:* 1 –> 2 &#…

Given a non-negative integer num, repeatedly add all its digits until the result has only one digit. For examp…

369- Plus One Linked List **Question Editorial Solution My Submissions Total Accepted: 1189 Total Submissions:…

  Divide two integers without using multiplication, division and mod operator. If it is overflow, return …

  Given the root node of a binary search tree (BST) and a value. You need to find the node in the BST tha…

题目： Given n, how many structurally unique BST’s (binary search trees) that store values 1…

1. 题目 Given a non-negative number represented as an array of digits, plus one to the number. The digits are st…

Straight-forward solution. O(n) space, O(1)(get) + O(nlogn)(sort the array before getting median) time solutio…

Java语言也许是在设计之初有一点点没有完全计划好，导致各种不同的数据类型在获取长度的时候方法完全不同。相较于Python，几乎所有有长度的变量都可以用len()来获取长度。 String类 String test_st…

再一次理解错题意. peek() 就是头顶，但是不一定是最大值啊。总是把PEEK想成了最大值，然后用2 STACK做了最大值的cache，练的一手好双stack，可惜错了。 回到原题，其实不难。找一个cache来存nex…

题目 Given numRows, generate the first numRows of Pascal’s triangle. For example, given numRows = 5, Retur…

题目 We define a harmonious array is an array where the difference between its maximum value and its minimum val…