Leetcode:Best Time to Buy and Sell Stock

Say you have an array for which the ith element is the price of a given stock on day i.

If you were only permitted to complete at most one transaction (ie, buy one and sell one share of the stock), design an algorithm to find the maximum profit.

分析：貪心算法。記錄前面出現的price的最小值，而後用max(maxProfit, prices[i] - min)更新最大收益。代碼以下：

class Solution {
public:
    int maxProfit(vector<int> &prices) {
        int maxPro = 0;
        int minPri = INT_MAX;
        
        for(int i = 0; i < prices.size(); i++){
            if(prices[i] < minPri) minPri = prices[i];
            else maxPro = max(maxPro, prices[i]-minPri);
        }
        
        return maxPro;
    }
};