Best Time to Buy and Sell Stock IV

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 k transactions.

class Solution {
public:
    int maxProfit(int k, vector<int>& prices) {
        if(prices.size() <= 1)  return 0;
        int n = prices.size();
        //此处如果k的次数超过了数组长度的一半
        if(k > n/2)   return quickSolve(prices);

        int trans = k;
        vector<vector<int>> dp(trans + 1, vector<int>(prices.size(), 0));

        for(int kk = 1; kk <= trans; kk++){
            int tmpMax = dp[kk - 1][0] - prices[0];
            for(int i = 1; i < prices.size(); i++){
                dp[kk][i] = max(dp[kk][i - 1],prices[i]+tmpMax);
                tmpMax = max(tmpMax,dp[kk - 1][i] - prices[i]);
            }
        }
        return dp[k][n - 1];
    }
    int quickSolve(vector<int> &p){
        int res = 0;
        for(int i = 1; i < p.size(); i++){
            if(p[i] > p[i - 1]) res += p[i] - p[i - 1];
        }

        return res;
    }
};