剑指 Offer 63. 股票的最大利润

class Solution {
public:
    int maxProfit(vector<int>& prices) {
        if(prices.size() <=0 ){
            return 0;
        }
        int min_price = prices[0];
        int profit = 0;
        for(int i = 1; i<prices.size(); i++){
            min_price = min(min_price, prices[i]);
            profit = max(profit, prices[i] - min_price);
        }
        return profit;
    }
};