原题链接在这里:https://leetcode.com/problems/valid-word-square/ 题目: Given a sequence of words, check whether it forms a valid word square. A sequence of words forms a valid word square if the kth row and column read the exact same string, where 0 ≤ k < max(…

作者: 负雪明烛 id: fuxuemingzhu 个人博客:http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 拼接出每一列的字符串 日期 题目地址:https://leetcode-cn.com/problems/valid-word-square/ 题目描述 Given a sequence of words, check whether it forms a valid word square. A sequence of words forms a va…

似乎可以沿着对角线往右往下检查,也可以正常按题设检查. 我用的后者.. public class Solution { public boolean validWordSquare(List<String> words) { if(words.size() <= 1) return true; if(words.size() != words.get(0).length()) return false; for(int i = 0; i < words.get(0).length(…

Given a sequence of words, check whether it forms a valid word square. A sequence of words forms a valid word square if the kth row and column read the exact same string, where 0 ≤k < max(numRows, numColumns). Note: The number of words given is at le…

Given a sequence of words, check whether it forms a valid word square. A sequence of words forms a valid word square if the kth row and column read the exact same string, where 0 ≤ k < max(numRows, numColumns). Note: The number of words given is at l…

Given a sequence of words, check whether it forms a valid word square. A sequence of words forms a valid word square if the kth row and column read the exact same string, where 0 ≤ k < max(numRows, numColumns). Note: The number of words given is at l…

原题: 367. Valid Perfect Square 读题: 求一个整数是否为完全平方数,如1,4,9,16,……就是完全平方数,这题主要是运算效率问题 求解方法1:812ms class Solution { public: bool isPerfectSquare(int num) { if(num < 0) return false; int i = 0; //这里要加1,不然num = 1时会出错 for(;i< num/2 + 1;i++) { if(i*i == num) {…

Leetcode之二分法专题-367. 有效的完全平方数(Valid Perfect Square) 给定一个正整数 num,编写一个函数,如果 num 是一个完全平方数,则返回 True,否则返回 False. 说明:不要使用任何内置的库函数,如  sqrt. 示例 1: 输入:16 输出:True 示例 2: 输入:14 输出:False 不能用sqrt,判断一个数是否是一个完全平方数. 1.可以用for循环,但时间复杂度高2.用二分法,思路如下: 从0-N,取中点 看中点的平方是否大于nu…

367. Valid Perfect Square Easy Given a positive integer num, write a function which returns True if num is a perfect square else False. Note: Do not use any built-in library function such as sqrt. Example 1: Input: 16 Output: true Example 2: Input: 1…

Given a non-empty string s and an abbreviation abbr, return whether the string matches with the given abbreviation. A string such as "word" contains only the following valid abbreviations: ["word", "1ord", "w1rd", &…

Given a non-empty string s and an abbreviation abbr, return whether the string matches with the given abbreviation. A string such as "word" contains only the following valid abbreviations: ["word", "1ord", "w1rd", &…

Given a non-empty string s and an abbreviation abbr, return whether the string matches with the given abbreviation. A string such as "word" contains only the following valid abbreviations: ["word", "1ord", "w1rd", &…

［抄题］: Given a non-empty string s and an abbreviation abbr, return whether the string matches with the given abbreviation. A string such as "word" contains only the following valid abbreviations: ["word", "1ord", "w1rd&qu…

作者: 负雪明烛 id: fuxuemingzhu 个人博客:http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 双指针 日期 题目地址:https://leetcode-cn.com/problems/valid-word-abbreviation/ 题目描述 Given a non-empty string s and an abbreviation abbr, return whether the string matches with the given…

Given a positive integer num, write a function which returns True if num is a perfect square else False. Note: Do not use any built-in library function such as sqrt. Example 1: Input: 16 Returns: True Example 2: Input: 14 Returns: False Credits:Speci…

Given a positive integer num, write a function which returns True if num is a perfect square else False. Note: Do not use any built-in library function such as sqrt. Example 1: Input: 16 Returns: True Example 2: Input: 14 Returns: False 本题可以用binary s…

Given a positive integer num, write a function which returns True if num is a perfect square else False. Note: Do not use any built-in library function such as sqrt. Example 1: Input: 16 Returns: True Example 2: Input: 14 Returns: False 分析:二分.注意溢出! p…

题目描述: Given a positive integer num, write a function which returns True if num is a perfect square else False. 解题分析: 这种找数字的题一般都用类似与二分查找的算法.需要注意的是比较平方和时考虑到integer溢出的情况.所以这个结果是要用Long类型保存.由此到来的改变是判断相等时要用“equals()”方法,而不是“==”. 实现代码: public class Solution…

感冒之后 睡了2天觉 现在痊愈了 重启刷题进程.. Google的题,E难度.. 比较的方法很多,应该是为后面的题铺垫的. 题不难,做对不容易,edge cases很多,修修改改好多次,写完发现是一坨. 奉劝大家尽量多想edge cases,想不出来了再提交,别像我似的赶着投胎就提交了. 想完了先自己试试下面这些test cases... "internationalization" "i12iz4n" "word" "1or1&quo…

Given a positive integer num, write a function which returns True if num is a perfect square else False. Note: Do not use any built-in library function such as sqrt. Example 1: Input: 16 Output: true Example 2: Input: 14 Output: false 给定一个正整数 num,编写一…

Given a positive integer num, write a function which returns True if num is a perfect square else False. Note: Do not use any built-in library function such as sqrt. Example 1: Input: 16 Returns: True Example 2: Input: 14 Returns: False 题意: 验证完全平方数 思…

［抄题］: Given a positive integer num, write a function which returns True if num is a perfect square else False. Note: Do not use any built-in library function such as sqrt. Example 1: Input: 16 Returns: True Example 2: Input: 14 Returns: False [暴力解法]:…

Given a positive integer num, write a function which returns True if num is a perfect square else False. Note: Do not use any built-in library function such as sqrt. Example 1: Input: 16 Returns: True Example 2: Input: 14 Returns: False Credits:Speci…

Given a positive integer num, write a function which returns True if num is a perfect square else False. Note: Do not use any built-in library function such as sqrt. Example 1: Input: 16 Output: true Example 2: Input: 14 Output: false class Solution…

问题 该文章的最新版本已迁移至个人博客[比特飞],单击链接 https://www.byteflying.com/archives/3869 访问. 给定一个正整数 num,编写一个函数,如果 num 是一个完全平方数,则返回 True,否则返回 False. 说明:不要使用任何内置的库函数,如  sqrt. 输入:16 输出:True 输入:14 输出:False Given a positive integer num, write a function which returns True…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 方法一:完全平方式性质 方法二:暴力求解 方法三:二分查找 方法四:牛顿法 日期 题目地址:https://leetcode.com/problems/valid-perfect-square/description/ 题目描述 Given a positive integer num, write a function which returns…

Typical binary search.. but take care of data overflow if you are using C++ class Solution { public: bool isPerfectSquare(int num) { ) return false; ) return true; , j = num - ; while(i <= j) { ; long long r = mid * mid; if(r == num) return true; ; ;…

题目描述:给出一个正整数,不使用内置函数,如sqrt(),判断这个数是不是一个数的平方. 思路:直接使用二分法,貌似没啥好说的.代码如下: class Solution(object): def isPerfectSquare(self, num): """ :type num: int :rtype: bool """ left, right = 0, num while left <= right: mid = (left+right)…

class Solution { public: bool isPerfectSquare(int num) { /* //方法一:蜜汁超时…… if (num < 0) return false; if (num == 1) return true; for (int i=1;i*i<=num;i++){ if (i*i==num) return true; } return false; }*/ /* //方法二:是对的! if(num < 0) return false; if(n…

这是悦乐书的第209次更新,第221篇原创 01 看题和准备 今天介绍的是LeetCode算法题中Easy级别的第77题(顺位题号是367).给定正整数num,写一个函数,如果num是一个完美的正方形,则返回True,否则返回False.例如: 输入:16 输出:true 输入:14 输出:false 注意:不要使用任何内置库函数,例如sqrt. 本次解题使用的开发工具是eclipse,jdk使用的版本是1.8,环境是win7 64位系统,使用Java语言编写和测试. 02 第一种解法 暴力解法…