随笔分类 - OJ
摘要：题目链接Given an input string, reverse the string word by word.For example,Given s = "the sky is blue",return "blue is sky the". 1 class Solution { 2 publ...
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摘要：题目链接给定两个正整数a,b，分别定义两个集合L和R，集合L：即把1~a，1~b中整数乘积的集合定义为L = {x * y | x,y是整数且1 b 可以两者交换)，a的十进制位数为ka, b的十进制位数为kb。因此异或求解集合R中元素时，只有b的最后ka个二进制位受影响，b的前kb-ka个二进制位可以表示0…2^(kb-ka)-1的所有数。现在我们只考虑b的后面ka个二进制位：1、假设b = 11001，a = 101，那么R = {00001…11001}^{001…101}表示的数有哪些呢？ 我们可以看到两者异或后可以表示的最大的数是11001^100 = 11101（注意到后三位异或.
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摘要：题目如下甲乙两个人用一个英语单词玩游戏。两个人轮流进行，每个人每次从中删掉任意一个字母，如果剩余的字母序列是严格单调递增的（按字典序a Map; static int who (string word) { //用map保存子问题，防止重复计算 //amap[s]表示字符串s由甲操作时甲能否获胜 //bmap[s]表示字符串s由乙操作时甲能否获胜 Map amap, bmap; return (int)dfs(word, 1, amap, bmap); }private: //判断字符串是否严格...
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摘要：题目链接Given two binary strings, return their sum (also a binary string).For example, a = "11" b = "1" Return "100".分析：简单的处理二进制求和和进位即可 本文地址class So...
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摘要：题目链接Validate if a given string is numeric.Some examples: "0" => true " 0.1 " => true "abc" => false "1 a" => false "2e10" => true 本文地址Note...
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摘要：题目链接Given a number represented as an array of digits, plus one to the number分析：too simple 本文地址class Solution {public: vector plusOne(vector &digits...
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摘要：题目链接Given an array of words and a length L, format the text such that each line has exactly L characters and is fully (left and right) justified.You s...
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摘要：题目链接Implement int sqrt(int x).Compute and return the square root of x.面试时需要考虑x是否小于0.分析：牛顿法，先假设一个初始解res（本文设为1），然后以抛物y = x^2-c（这里的c相当于题目中的x）上的点(res, res...
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摘要：题目链接You are climbing a stair case. It takes n steps to reach to the top.Each time you can either climb 1 or 2 steps. In how many distinct ways can you...
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摘要：题目链接Given an absolute path for a file (Unix-style), simplify it.For example, path = "/home/", => "/home" path = "/a/./b/../../c/", => "/c"Corner Ca...
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摘要：题目链接Given two words word1 and word2, find the minimum number of steps required to convert word1 to word2. (each operation is counted as 1 step.)You ha...
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摘要：题目链接Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place.Follow up:Did you use extra space? A straight forward...
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摘要：LeetCode:Search in Rotated Sorted ArraySuppose a sorted array is rotated at some pivot unknown to you beforehand.(i.e., 0 1 2 4 5 6 7 might become 4 5...
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摘要：题目链接Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties:Integers in each row are sorte...
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摘要：题目链接Given an array with n objects colored red, white or blue, sort them so that objects of the same color are adjacent, with the colors in the order r...
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摘要：题目链接Given two integers n and k, return all possible combinations of k numbers out of 1 ... n.For example, If n = 4 and k = 2, a solution is:[ [2,4], ...
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摘要：题目链接Given a 2D board and a word, find if the word exists in the grid.The word can be constructed from letters of sequentially adjacent cell, where "ad...
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摘要：LeetCode:Remove Duplicates from Sorted ListGiven a sorted linked list, delete all duplicates such that each element appear only once.For example, Give...
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摘要：LeetCode:Remove Duplicates from Sorted ArrayGiven a sorted array, remove the duplicates in place such that each element appear only once and return th...
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摘要：题目链接Given a string S and a string T, find the minimum window in S which will contain all the characters in T in complexity O(n).For example, S = "ADOB...
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