[LeetCode] Best Time to Buy and Sell Stock III

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

Design an algorithm to find the maximum profit. You may complete at most two transactions.

Note:
You may not engage in multiple transactions at the same time (ie, you must sell the stock before you buy again).

class Solution {public:    int maxProfit(vector<int> &prices) {        int n = prices.size(), profit = 0;        if(n == 0)  return 0;        int l[n], r[n];        memset(l, 0, sizeof(int) * n);        memset(r, 0, sizeof(int) * n);        int min = prices[0];        for(int i = 1; i < n; i++)        {            l[i] = prices[i] - min > l[i - 1] ? prices[i] - min : l[i - 1];            min = prices[i] < min ? prices[i] : min;        }        int max = prices[n - 1];        for(int i = n - 2; i >= 0; i--)        {            r[i] = max - prices[i] > r[i + 1] ? max - prices[i] : r[i + 1];            max = prices[i] > max ? prices[i] : max;        }        for(int i = 0; i < n; i++)            profit = l[i] + r[i] > profit ? l[i] + r[i] : profit;        return profit;    }};