Best time to buy and sell stock 3

#include <bits/stdc++.h> 

// int f(int i, int buy, int cap, int n, vector<int> &prices, vector<vector<vector<int>>> &dp){
//     if(cap == 0) return 0;
//     if(i == n) return 0;
//     if(dp[i][buy][cap] != -1) return dp[i][buy][cap];
//     if(buy){
//         return dp[i][buy][cap] = max(-prices[i] + f(i+1, 0, cap, n, prices, dp), 0 + f(i+1, 1, cap, n, prices, dp));
//     }
//     else{
//         return dp[i][buy][cap] = max(prices[i] + f(i+1, 1, cap-1, n, prices, dp), 0 + f(i+1, 0, cap, n, prices, dp));
//     }
// }

int maxProfit(vector<int>& prices, int n)
{
//     vector<vector<vector<int>>> dp(n, vector<vector<int>>(2, vector<int>(3, -1)));
//     return f(0, 1, 2, n, prices, dp);
       // Write your code here.
    vector<vector<vector<int>>> dp(n+1, vector<vector<int>>(2, vector<int>(3, 0)));
    for(int i=n-1;i>=0;i--){
        for(int buy=0;buy<=1;buy++){
            for(int cap=1;cap<=2;cap++){
                if(buy){
                    dp[i][buy][cap] = max(-prices[i] + dp[i+1][0][cap], 0 + dp[i+1][1][cap]);
                }
                else{
                    dp[i][buy][cap] = max(prices[i] + dp[i+1][1][cap-1], 0 + dp[i+1][0][cap]);
                }
            }
        }
    }
    return dp[0][1][2];
}