class Solution {
public:
    int maxProfit(int k, vector<int>& prices) {
        auto s=prices.size();
        if(s<=1)
            return 0;

        if(2*k>=s)
        {
            int result=0;
            for(int i=1;i<s;++i)
            {
                auto t=prices[i]-prices[i-1];
                if(t>0)
                    result+=t;
            }
            return result;
        }
        vector<vector<int>> dp(k+1,vector<int>(s,0));

        for(int i=1;i<=k;++i)
        {
            int buy=dp[i-1][0]-prices[0];
            for(int j=1;j<s;++j)
            {
                dp[i][j]=max(dp[i][j-1],prices[j]+buy);
                buy=max(buy,dp[i-1][j]-prices[j]);
            }
        }
        return dp[k][s-1];
    }
};