好久没切 leetcode 的题了,静下心来切了道,这道题比较有意思,和大家分享下. 我把它叫做 "不一样的猜数字游戏",我们先来看看传统的猜数字游戏,Guess Number Higher or Lower.题意非常的简单,给定一个数字 n,系统会随机从 1 到 n 中抽取一个数字,你需要写一个函数 guessNumber,它的作用是返回系统选择的数字,同时你还有一个外部的 API 可以调用,是为 guess 函数,它会将你猜的数字和系统选择的数字比较,是大了还是小了. 非常的简单,…

We are playing the Guess Game. The game is as follows: I pick a number from 1 to n. You have to guess which number I picked. Every time you guess wrong, I'll tell you whether the number I picked is higher or lower. However, when you guess a particula…

[LeetCode]375. Guess Number Higher or Lower II 解题报告(Python) 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址: https://leetcode.com/problems/guess-number-higher-or-lower-ii/description/ 题目描述: We are playing the Guess Game. The game is as f…

这是在看geeksforgeeks时看到的一道题,挺不错的,题目是 Given a number system with only 3 and 4. Find the nth number in the number system. First few numbers in the number system are: 3, 4, 33, 34, 43, 44, 333, 334, 343, 344, 433, 434, 443, 444, 3333, 3334, 3343, 3344, 343…

odd number 奇数 even number 偶数…

最近在优化一个页面时候.IDEA 提示我错误的使用了包装类.当时感觉很诧异. 随后.我上Stack Overflow上面查了一下,终于发现了问题所在. new Number('123') 与 Number('123') 是有很大区别的. 具体来说就是:new Number('123') 会返回一个包装过的对象,类似于Java中的Integer类型,而 Number('123') 会返回一个原始的数字类型,相当于Java中的int类型.虽然内容相等,但是在后面判断时,可能会产生误解. 随后我在Ch…

ES6在Number对象上,新提供了Number.isFinite()和Number.isNaN()两个方法,用来检查Infinite和NaN这两个特殊值. Number.isFinite()用来检查一个数值是否非无穷(infinity). Number.isFinite(15); // true Number.isFinite(0.8); // true Number.isFinite(NaN); // false Number.isFinite(Infinity); // false Num…

在回答园子问题的时候发现了不少新东西,写下来分享一下 == 下面的图就是此篇的概览,另外文章的解释不包括ES6新增的Symbol,话说这货有包装类型,但是不能new... 基于JS是面向对象的,所以我们称呼function为“方法”,等同于“函数”. 1.Number与Number Object ——原始类型与包装类型(primitive VS wrapper object) ECMAScript定义了7种数据类型:6种原始类型(ES6新增Symbol)以及Object.原始类型(primiti…

136. Single Number Given an array of integers, every element appears twice except for one. Find that single one. (Easy) Note:Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory? 分析: 第一问属于技巧题,做过就会,…

how to convert a number to a number array in javascript without convert number to a string 如何在不将数字转换为一个字符串的情况下将一数字转换为javascript中的一个数字数组 Number To Array Math.round 四舍五入 bug "use strict"; /** * * @author xgqfrms * @license MIT * @copyright xgqfrms…

[] Given an array of integers, every element appears twice except for one. Find that single one. [] Given an array of integers, every element appears three times except for one. Find that single one. (better solution is needed) Note: Your algorithm s…

leetcode 136. Single Number Given an array of integers, every element appears twice except for one. Find that single one. Note: Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory? 解题思路: 如果以线性复杂度和…

We are playing the Guess Game. The game is as follows: I pick a number from 1 to n. You have to guess which number I picked. Every time you guess wrong, I'll tell you whether the number I picked is higher or lower. However, when you guess a particula…

Given a boolean 2D matrix, find the number of islands. Notice 0 is represented as the sea, 1 is represented as the island. If two 1 is adjacent, we consider them in the same island. We only consider up/down/left/right adjacent. Example Given graph: […

We are playing the Guess Game. The game is as follows: I pick a number from 1 to n. You have to guess which number I picked. Every time you guess wrong, I'll tell you whether the number I picked is higher or lower. However, when you guess a particula…

We are playing the Guess Game. The game is as follows: I pick a number from 1 to n. You have to guess which number I picked. Every time you guess wrong, I'll tell you whether the number I picked is higher or lower. However, when you guess a particula…

e are playing the Guess Game. The game is as follows: I pick a number from 1 to n. You have to guess which number I picked. Every time you guess wrong, I'll tell you whether the number I picked is higher or lower. However, when you guess a particular…

Given a non-empty 2D array grid of 0's and 1's, an island is a group of 1's (representing land) connected 4-directionally (horizontal or vertical.) You may assume all four edges of the grid are surrounded by water. Count the number of distinct island…

We are playing the Guess Game. The game is as follows: I pick a number from 1 to n. You have to guess which number I picked. Every time you guess wrong, I'll tell you whether the number I picked is higher or lower. However, when you guess a particula…

We are playing the Guess Game. The game is as follows: I pick a number from 1 to n. You have to guess which number I picked. Every time you guess wrong, I'll tell you whether the number I picked is higher or lower. However, when you guess a particula…

Given a non-empty 2D array grid of 0's and 1's, an island is a group of 1's (representing land) connected 4-directionally (horizontal or vertical.) You may assume all four edges of the grid are surrounded by water. Count the number of distinct island…

We are playing the Guess Game. The game is as follows: I pick a number from 1 to n. You have to guess which number I picked. Every time you guess wrong, I'll tell you whether the number I picked is higher or lower. However, when you guess a particula…

374. Guess Number Higher or Lower 二分查找就好 // Forward declaration of guess API. // @param num, your guess // @return -1 if my number is lower, 1 if my number is higher, otherwise return 0 int guess(int num); class Solution { public: int guessNumber(int…

Given a non-empty 2D array grid of 0's and 1's, an island is a group of 1's (representing land) connected 4-directionally (horizontal or vertical.) You may assume all four edges of the grid are surrounded by water. Count the number of distinct island…

最后更新 四刷? 极大极小算法..还是叫极小极大的.. 首先要看怎么能保证赢. 比如2个数,猜第一个猜第二个都能保证下一轮我们赢定了,为了少交钱,我们猜小的. 比如3个数,猜第二个才能保证下一轮再猜一定能赢. 比如4个数,怎么猜都不能保证下一轮一定赢,所以要猜两轮.第一轮猜1,2,3还是4就很讲究了. 猜1就是num1 + dp[2][4](今后花费) 猜2就是dp[1][1](今后花费) + num2或者num[1] + dp[3][4](今后花费) ... 4种里每种都算出来,看哪种花费最少…

▶ 三个与丑数相关的问题 ▶ 第 263题,判定一个数字是否是丑数,即其素因子是否仅由 2,3,5 构成. ● 常规消除判别,4 ms class Solution { public: bool isUgly(int num) { ) return false; ); num /= ); ); num /= ); ); num /= ); ; } }; ● 递归方法,6 ms class Solution { public: bool isUgly(int num) { ) return fal…

我们正在玩一个猜数游戏,游戏规则如下:我从 1 到 n 之间选择一个数字,你来猜我选了哪个数字.每次你猜错了,我都会告诉你,我选的数字比你的大了或者小了.然而,当你猜了数字 x 并且猜错了的时候,你需要支付金额为 x 的现金.直到你猜到我选的数字,你才算赢得了这个游戏.示例:n = 10, 我选择了8.第一轮: 你猜我选择的数字是5,我会告诉你,我的数字更大一些,然后你需要支付5块.第二轮: 你猜是7,我告诉你,我的数字更大一些,你支付7块.第三轮: 你猜是9,我告诉你,我的数字更小一些,你支付…

思路: dp. https://leetcode.com/problems/guess-number-higher-or-lower-ii/discuss/ 实现: class Solution { public: int getMoneyAmount(int n) { ][n + ]; memset(dp, 0x3f, sizeof dp); ; i <= n; i++) dp[i][i] = ; ; i >= ; i--) { ; j <= n; j++) { for (int k…

原题 思路: miniMax+DP dp[i][j]保存在i到j范围内,猜中这个数字需要花费的最少 money. "至少需要的花费",就要我们 "做最坏的打算,尽最大的努力",即取最大值. dp[beg][end] =MIN ( i + max(helper(beg, i - 1, dp), helper(i + 1, end, dp)) ) class Solution { public: int helper(int beg, int end, vector&l…

简介: 使用位移法将ip转为number型以及将number型转为ip,使用语言为python2.7 #!/usr/bin/env python # coding:utf-8 def ip2num(ip):     ip = [int(x) for x in ip.split('.')]     return ip[0] << 24 | ip[1] << 16 | ip[2] << 8 | ip[3] print ip2num('10.101.101.13') #174…