问题描述: 在股市的交易日中,假设最多可进行两次买卖(即买和卖的次数均小于等于2),规则是必须一笔成交后进行另一笔(即买-卖-买-卖的顺序进行).给出一天中的股票变化序列,请写一个程序计算一天可以获得的最大收益.请采用实践复杂度低的方法实现. 给定价格序列prices及它的长度n,请返回最大收益.保证长度小于等于500. class Solution { public: int maxProfit(vector<int>& prices) { //It's wrong if you c…
Given an integer array with all positive numbers and no duplicates, find the number of possible combinations that add up to a positive integer target. Example: nums = [1, 2, 3] target = 4 The possible combination ways are: (1, 1, 1, 1) (1, 1, 2) (1,…
Given a range [m, n] where 0 <= m <= n <= 2147483647, return the bitwise AND of all numbers in this range, inclusive. For example, given the range [5, 7], you should return 4. 题解:如果m==n,那么答案就是m. 如果m<n,那么二进制最右边一位在最后的结果中肯定是0,那么就可以转化成子问题: rangeBi…