方法一

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