You are given two linked lists representing two non-negative numbers. The digits are stored in reverse order and each of their nodes contain a single digit. Ad...

要点 本题考查的是整数相加的溢出处理，检查溢出有这么几种办法： – 两个正数数相加得到负数，或者两个负数相加得到正数，但某些编译器溢出或优化的方式不一样 – 对于正数，如果最大整数减去一个数小于另一个数，或者对于负数，...

本文介绍string模块ascii_letters和digits方法，其中ascii_letters是生成所有字母，从a-z和A-Z,digits是生成所有数字0-9.示例如下：In [2]: chars = string.ascii_letters + string.digitsIn [3]: print(c......

题目没有说清楚，trick挺多，考察细心程度的水题吧。 You are given two linked lists representing two non-negative numbers. The digits are stored in reverse order and each of their n......

Reverse digits of an integer. Example1: x = 123, return 321 Example2: x = -123, return -321Easy，没什么好说的注意负数和溢出的情况class Solution {public: int reverse(...

Given a non-negative number represented as an array of digits, plus one to the number. The digits are stored such that the most significant digit is at the he...

Write an algorithm to determine if a number is "happy". A happy number is a number defined by the following process: Starting with any positive integer, repla...

You are playing the following Bulls and Cows game with your friend: You write down a number and ask your friend to guess what the number is. Each time your fr...

该文是关于二叉树的问题，给定一个代表数字的树，需要求出从根结点到叶子结点的所有路径的和。和Path Sum II类似，只不过需要累加的是每个路径代表的数字。通过递归的方式，对每个结点进行遍历，如果该结点有左右子结点，则递归...

该文讲述了如何利用单调栈实现一个高效的算法，求解输入整数N的最大单调递增数字。该算法的时间复杂度为O(n)，其中n是输入整数N的位数。该算法利用了单调栈的特性：当从左到右扫描数组时，如果栈顶元素等于当前遍历的元素，那...