121. 买卖股票的最佳时机
【参考代码】
动态规划解决
class Solution {
public:int maxProfit(vector<int>& prices) {int size = prices.size();int min_price = 99999, max_profit = 0;for(int i=0; i<size; i++){if(prices[i] < min_price){min_price = prices[i];}else if(prices[i] - min_price > max_profit){max_profit = prices[i] - min_price;}}return max_profit;}
};
125. 验证回文串
【参考代码】
class Solution {
public:bool isPalindrome(string s) {string s1 = "";int size = s.size();if(size == 0){return true;}for(char c : s){if(isalnum(c)){s1 += tolower(c);}}string temp = s1;reverse(temp.begin(), temp.end());if(temp == s1){return true;}else{return false;}}
};