原题地址:http://oj.leetcode.com/problems/valid-number/ 题意:判断输入的字符串是否是合法的数. 解题思路:这题只能用确定有穷状态自动机(DFA)来写会比较优雅.本文参考了http://blog.csdn.net/kenden23/article/details/18696083里面的内容,在此致谢! 首先这个题有9种状态: 0初始无输入或者只有space的状态1输入了数字之后的状态2前面无数字,只输入了dot的状态3输入了符号状态4前面有数字和有do…

Valid Number Validate if a given string is numeric. Some examples:"0" => true" 0.1 " => true"abc" => false"1 a" => false"2e10" => true Note: It is intended for the problem statement to be am…

Valid NumberValidate if a given string is numeric. Some examples:"0" => true" 0.1 " => true"abc" => false"1 a" => false"2e10" => trueNote: It is intended for the problem statement to be ambi…

Validate if a given string is numeric. Some examples:"0" => true" 0.1 " => true"abc" => false"1 a" => false"2e10" => true Note: It is intended for the problem statement to be ambiguous. You…

原题地址:https://oj.leetcode.com/problems/valid-palindrome/ 题意: Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases. For example,"A man, a plan, a canal: Panama" is a palindrome."race a c…

Validate if a given string is numeric. Some examples: "0" => true " 0.1 " => true "abc" => false "1 a" => false "2e10" => true Note: It is intended for the problem statement to be ambiguous.…

Validate if a given string is numeric. Some examples:"0" => true" 0.1 " => true"abc" => false"1 a" => false"2e10" => true Note: It is intended for the problem statement to be ambiguous. You…

题意:判断一个字符串是否是一个合法的数字,包括正负浮点数和整形. 思路:有限自动机可以做,画个图再写程序就可以解决啦,只是实现起来代码的长短而已. 下面取巧来解决,分情况讨论: (1)整数 (2)浮点数 (3)整数e整数 (4)浮点数e整数 只有以上4种情况.但是要数之前可能带1个符号,这个可以直接过滤1个,而不影响结果.而且,其包含关系是从上到下扩展的,(1)扩展到(2),(3)扩展到 (4). 那么先解决符号 e 之前的,必须满足:正负号至多1个,有数字1个以上,点至多1个. 如果没有e,那…

#数独(すうどく,Sūdoku)是一种运用纸.笔进行演算的逻辑游戏.玩家需要根据9×9盘面上的已知数字,推理出所有剩余空格的数字,并满足每一行.每一列.每一个粗线宫内的数字均含1-9,不重复.#数独盘面是个九宫,每一宫又分为九个小格.在这八十一格中给出一定的已知数字和解题条件,利用逻辑和推理,在其他的空格上填入1-9的数字.使1-9每个数字在每一行.每一列和每一宫中都只出现一次,所以又称“九宫格”. # http://sudoku.com.au/TheRules.aspx class Solut…

#question : 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? class Solution(object): def si…