題目： A message containing letters from A-Z is being encoded to numbers using the following mapping way: 'A' -> 1 'B' -> 2 ... 'Z' -> 26 Beyond that, now the encoded string can also contain the character ‘*’, whic

Sort a linked list using insertion sort. 鏈表的插入排序，其實有2種特殊情況： 1、插入的值插入到已排序的末尾。 leetcode并查集，2、插入的值插入到已排序的最前端。 主要設置了3個指針。 1、pStart是已排序鏈表的開始位置。 2、pInsert是待插入的位置。 LE

原題鏈接在這里：https://leetcode.com/problems/word-ladder/ leetcode70。題目： Given two words (beginWord?and?endWord), and a dictionary's word list, find the length of shortest transformation sequence from?beginWord?to?endWord, such that:

題目連接 https://leetcode.com/problems/course-schedule-ii/?? Course Schedule II Description There are a total of n courses you have to take, labeled from 0 to n - 1. leetcode 課程表？Some courses may have prerequisites, for example to take course 0 you ha

Write a program to find the node at which the intersection of two singly linked lists begins. For example, the following two linked lists: A: a1 → a2 ↘ c1 → c2 → c3 ↗ B: b1 → b2 → b3 begin to intersect at node c1. /*** Definition for singly-linked

原題鏈接在這里：https://leetcode.com/problems/remove-k-digits/description/ 題目： Given a non-negative integer?num?represented as a string, remove?k?digits from the number so that the new number is the smallest possible. Note: The length of?nu

Intersection of Two Linked Lists: Write a program to find the node at which the intersection of two singly linked lists begins. For example, the following two linked lists: A: a1 → a2↘c1 → c2 → c3↗ B: b1 → b2 → b3 leetcode121，begin to intersect at

題目鏈接：?https://leetcode.com/problems/reverse-nodes-in-k-group/?tab=Description Problem ：將一個有序list劃分為k個組，并且每個組的元素逆置 鏈表操作 ：遞歸算法? 每次尋找到該組的尾部，然后進行逆置操作，返回頭部

傳送門 Description Given an integer (signed 32 bits), write a function to check whether it is a power of 4. Example:Given num = 16, return true. Given num = 5, return false. Follow up: Could you solve it without loops/recursion? 思路 題意：不

題目出處：https://leetcode.com/problems/basic-calculator/題意描述： 給定一個只含加減號，括號，空格和非負數的合法字符串，在不調用庫函數eval的條件下求出其值 解決思路： 由于此題只有加減號，因此不存在運算符優先級的問題