喵星人与汪星人

摘要： Validate Binary Search TreeGiven a binary tree, determine if it is a valid binary search tree (BST).Assume a BST is defined as follows:The left subtre... 阅读全文

摘要： Pow(x, n)Implement pow(x,n).算法思路：二分法，没什么好说的，小心点就行；这个题时间比较苛刻。return pow(x,n >> 1) * pow(x,n >> 1) 是过不去的，因此把pow(x,n / 2)求出来先。其实时间复杂度而言，是一样的。【注意】：n的取值范围；... 阅读全文

摘要： Subsets IIGiven a collection of integers that might contain duplicates,S, return all possible subsets.Note:Elements in a subset must be in non-descend... 阅读全文

摘要： SubsetsGiven a set of distinct integers,S, return all possible subsets.Note:Elements in a subset must be in non-descending order.The solution set must... 阅读全文

摘要： Insert IntervalGiven a set ofnon-overlappingintervals, insert a new interval into the intervals (merge if necessary).You may assume that the intervals... 阅读全文

摘要： Merge IntervalsGiven a collection of intervals, merge all overlapping intervals.For example,Given[1,3],[2,6],[8,10],[15,18],return[1,6],[8,10],[15,18]... 阅读全文

摘要： Valid PalindromeGiven a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases.For example,"A man, a pla... 阅读全文

摘要： Merge Sorted ArrayGiven two sorted integer arrays A and B, merge B into A as one sorted array.Note:You may assume that A has enough space (size that i... 阅读全文

摘要： Length of Last WordGiven a stringsconsists of upper/lower-case alphabets and empty space characters' ', return the length of last word in the string.I... 阅读全文

摘要： Simplify PathGiven an absolute path for a file (Unix-style), simplify it.For example,path="/home/", =>"/home"path="/a/./b/../../c/", =>"/c"click to sh... 阅读全文