摘要： Implementatoito convert a string to an integer.Hint:Carefully consider all possible input cases. If you want a challenge, please do not see below and ask yourself what are the possible input cases.Notes:It is intended for this problem to be specified vaguely (ie, no given input specs). You are respo 阅读全文

摘要： Implement wildcard pattern matching with support for'?'and'*'.'?' Matches any single character.'*' Matches any sequence of characters (including the empty sequence).The matching should cover the entire input string (not partial).The function prototype should be:bool i 阅读全文

摘要： You are given a string,S, and a list of words,L, that are all of the same length. Find all starting indices of substring(s) in S that is a concatenation of each word in L exactly once and without any intervening characters.For example, given:S:"barfoothefoobarman"L:["foo", " 阅读全文

摘要： 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="ADOBECODEBANC"T="ABC"Minimum window is"BANC".Note:If there is no such window in S that covers all characters in T, return the emtpy 阅读全文

摘要： Sort a linked list inO(nlogn) time using constant space complexity.思路：归并排序。题目要求固定空间，不知道这种递归实现的算不算固定空间。代码： 1 ListNode *sortList(ListNode *head, int length){ 2 if(length next;14 }15 half = tmp->next;16 tmp->next = NULL;17 ListNode *first = sortList(head, l),... 阅读全文

摘要： Given 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].思路：先对数据进行排序，然后逐个插入。注意在使用sort的时候，最开始出现错误，后来把myCmp改成static的以后就解决了。代码： 1 int max(int a, int b){ 2 if(a > b) 3 return a; 4 return b; 5 ... 阅读全文

摘要： A message containing letters fromA-Zis being encoded to numbers using the following mapping:'A' -> 1'B' -> 2...'Z' -> 26Given an encoded message containing digits, determine the total number of ways to decode it.For example,Given encoded message"12", it cou 阅读全文

摘要： Evaluate the value of an arithmetic expression inReverse Polish Notation.Valid operators are+,-,*,/. Each operand may be an integer or another expression.Some examples: ["2", "1", "+", "3", "*"] -> ((2 + 1) * 3) -> 9 ["4", "13&qu 阅读全文

摘要： Divide two integers without using multiplication, division and mod operator.思路：直接的想法是用减法代替，但是减法在极端情况下肯定会超时，最多可能会有2^31。然后考虑用移位，对除数左移位，直到将要大于被除数时为止，然后记录当前值，并更新被除数，如此循环。需要注意的是，因为int的范围是-2^32到2^32，所以如果最小的负数取整数就会越界，所以使用unsigned int或者long long代替。代码： 1 int divide(int dividend, int divisor) { 2 ... 阅读全文

摘要： There areNchildren standing in a line. Each child is assigned a rating value.You are giving candies to these children subjected to the following requirements:Each child must have at least one candy.Children with a higher rating get more candies than their neighbors.What is the minimum candies you mu 阅读全文