shaer

摘要： Given a linked list, remove the n-th node from the end of list and return its head. Example: Note: Given n will always be valid. 方法一：双指针 删除倒数第n个点，我们首先 阅读全文

摘要： Given a sorted linked list, delete all duplicates such that each element appear only once. Example 1: Example 2: 方法二：直接前向传播 递归是从后往 前找，这个用while循环从前从后找。 阅读全文

摘要： Write a program to find the node at which the intersection of two singly linked lists begins. For example, the following two linked lists: begin to in 阅读全文

摘要： Given a positive integer n, find the least number of perfect square numbers (for example, 1, 4, 9, 16, ...) which sum to n. Example 1: Example 2: 时间复杂 阅读全文