Watch 10 video solutions for Find the Maximum Number of Fruits Collected, a hard level problem. This walkthrough by NeetCodeIO has 25,299 views views. Want to try solving it yourself? Practice on FleetCode or read the detailed text solution.
There is a game dungeon comprised of n x n rooms arranged in a grid.
You are given a 2D array fruits of size n x n, where fruits[i][j] represents the number of fruits in the room (i, j). Three children will play in the game dungeon, with initial positions at the corner rooms (0, 0), (0, n - 1), and (n - 1, 0).
The children will make exactly n - 1 moves according to the following rules to reach the room (n - 1, n - 1):
(0, 0) must move from their current room (i, j) to one of the rooms (i + 1, j + 1), (i + 1, j), and (i, j + 1) if the target room exists.(0, n - 1) must move from their current room (i, j) to one of the rooms (i + 1, j - 1), (i + 1, j), and (i + 1, j + 1) if the target room exists.(n - 1, 0) must move from their current room (i, j) to one of the rooms (i - 1, j + 1), (i, j + 1), and (i + 1, j + 1) if the target room exists.When a child enters a room, they will collect all the fruits there. If two or more children enter the same room, only one child will collect the fruits, and the room will be emptied after they leave.
Return the maximum number of fruits the children can collect from the dungeon.
Example 1:
Input: fruits = [[1,2,3,4],[5,6,8,7],[9,10,11,12],[13,14,15,16]]
Output: 100
Explanation:

In this example:
(0,0) -> (1,1) -> (2,2) -> (3, 3).(0,3) -> (1,2) -> (2,3) -> (3, 3).(3,0) -> (3,1) -> (3,2) -> (3, 3).In total they collect 1 + 6 + 11 + 16 + 4 + 8 + 12 + 13 + 14 + 15 = 100 fruits.
Example 2:
Input: fruits = [[1,1],[1,1]]
Output: 4
Explanation:
In this example:
(0,0) -> (1,1).(0,1) -> (1,1).(1,0) -> (1,1).In total they collect 1 + 1 + 1 + 1 = 4 fruits.
Constraints:
2 <= n == fruits.length == fruits[i].length <= 10000 <= fruits[i][j] <= 1000