无脑DP

#include<bits/stdc++.h>
using namespace std;

int maxProfit(int* prices, int pricesSize){
    if(pricesSize <= 1) return 0;
    int i = 0,* _prices,sum = 0;
    _prices = (int *)malloc(sizeof(int) * pricesSize);
    _prices[0] = 0;
    for(i = 1;i < pricesSize;i++){
        _prices[i] = prices[i] - prices[i - 1];
        if (_prices[i] > 0) sum += _prices[i]; 
    }
    return sum;
}

int main(){
    int pricesSize;
    cin >> pricesSize;
    int prices[pricesSize];
    for(int i = 0;i < pricesSize;i++)
        cin >> prices[i];
    cout << maxProfit(prices,pricesSize);
}