مشکل برنامه نویسی آموزش نینجا – جامعه dev

function(index, task) {
  if index = 0:
     go through the task
     track max
  return max;

  for all other index cases
     go through the task
     track the max by recursively going up through all possibilities
  return max at the end
}

import java.util.*;
public class Solution {
    public static int ninjaTraining(int n, int points[][]) {
        if (points == null || n == 0) {
            return 0;
        }
        // 0 means we have performed 0th activity running
        // 1 means we have performed fighting activity
        // 2 means we have performed learning activity
        // 3 means we haven't done any activity till now.
        return findMaxPoints(points, n - 1, 3);
    }

    private static int findMaxPoints(int [][] points, int index, int previousActivity) {
        if (index == 0) {
            int maxPoints = 0;
            int currentPoint = 0;
            for (int task = 0; task < 3; task++) {
                if (task != previousActivity) {
                    maxPoints = Math.max(maxPoints, points[0][task]);
                }
            }
            return maxPoints;
        }
        int maxPoints = 0;
        for (int task = 0; task < 3; task++) {
            if (task != previousActivity) {
                int pointsEarned = points[index][task] + findMaxPoints(points, index - 1, task);
                maxPoints = Math.max(maxPoints, pointsEarned);
            }
        }
        return maxPoints;
    }

}

import java.util.*;
public class Solution {
    public static int ninjaTraining(int n, int points[][]) {
        if (points == null || n == 0) {
            return 0;
        }
        // 0 means we have performed 0th activity running
        // 1 means we have performed fighting activity
        // 2 means we have performed learning activity
        // 3 means we haven't done any activity till now.
        int [][] dp = new int [n][4];
        for (int [] d : dp) {
            Arrays.fill(d, -1);
        }
        return findMaxPoints(points, n - 1, 3, dp);
    }

    private static int findMaxPoints(int [][] points, int index, int previousActivity, int [][] dp) {
        if (index == 0) {
            int maxPoints = 0;
            int currentPoint = 0;
            for (int task = 0; task < 3; task++) {
                if (task != previousActivity) {
                    maxPoints = Math.max(maxPoints, points[0][task]);
                }
            }
            return maxPoints;
        }
        if (dp[index][previousActivity] != -1) {
            return dp[index][previousActivity];
        }
        int maxPoints = 0;
        for (int task = 0; task < 3; task++) {
            if (task != previousActivity) {
                int pointsEarned = points[index][task] + findMaxPoints(points, index - 1, task, dp);
                maxPoints = Math.max(maxPoints, pointsEarned);
            }
        }
        return dp[index][previousActivity] = maxPoints;
    }

}

import java.util.*;
public class Solution {
    public static int ninjaTraining(int n, int points[][]) {
        if (points == null || n == 0) {
            return 0;
        }
        // 0 means we have performed 0th activity running
        // 1 means we have performed fighting activity
        // 2 means we have performed learning activity
        // 3 means we haven't done any activity till now.
        int [][] dp = new int [n][4];
        for (int [] d : dp) {
            Arrays.fill(d, -1);
        }
        dp[0][0] = Math.max(points[0][1], points[0][2]);
        dp[0][1] = Math.max(points[0][0], points[0][2]);
        dp[0][2] = Math.max(points[0][0], points[0][1]);
        dp[0][3] = Math.max(points[0][0], Math.max(points[0][1], points[0][2]));
        for (int index = 1; index < n; index++) {
            for (int last = 0; last < 4; last++) {
                int maximumPoint = 0;
                for (int task = 0; task < 3; task++) {
                    if (last != task) {
                        int pointsEarned = points[index][task] + dp[index - 1][task];
                        maximumPoint = Math.max(pointsEarned, maximumPoint);
                    }

                }
                dp[index][last] = maximumPoint;
            }
        }
        return dp[n - 1][3];
    }
}

import java.util.*;
public class Solution {
    public static int ninjaTraining(int n, int points[][]) {
        if (points == null || n == 0) {
            return 0;
        }
        // 0 means we have performed 0th activity running
        // 1 means we have performed fighting activity
        // 2 means we have performed learning activity
        // 3 means we haven't done any activity till now.
        int [][] dp = new int [n][4];
        for (int [] d : dp) {
            Arrays.fill(d, -1);
        }
        int [] previous = new int [4];
        int [] current = new int [4];
        previous[0] = Math.max(points[0][1], points[0][2]);
        previous[1] = Math.max(points[0][0], points[0][2]);
        previous[2] = Math.max(points[0][0], points[0][1]);
        previous[3] = Math.max(points[0][0], Math.max(points[0][1], points[0][2]));
        for (int index = 1; index < n; index++) {
            for (int last = 0; last < 4; last++) {
                int maximumPoint = 0;
                for (int task = 0; task < 3; task++) {
                    if (last != task) {
                        int pointsEarned = points[index][task] + previous[task];
                        maximumPoint = Math.max(pointsEarned, maximumPoint);
                    }

                }
                current[last] = maximumPoint;
            }
            int [] temp = previous;
            previous = current;
            current = temp;
        }
        return previous[3];
    }
}