3257. Maximum Value Sum by Placing Three Rooks II
Hard
50 Points
Array
Dynamic Programming
Matrix
Enumeration
You are given a m x n 2D array board representing a chessboard, where board[i][j] represents the value of the cell (i, j).
Rooks in the same row or column attack each other. You need to place three rooks on the chessboard such that the rooks do not attack each other.
Return the maximum sum of the cell values on which the rooks are placed.
Examples
Example 1
Input: board = [[-3,1,1,1],[-3,1,-3,1],[-3,2,1,1]]
Output: 4
Explanation:
We can place the rooks in the cells (0, 2) , (1, 3) , and (2, 1) for a sum of 1 + 1 + 2 = 4 .
Example 2
Input: board = [[1,2,3],[4,5,6],[7,8,9]]
Output: 15
Explanation:
We can place the rooks in the cells (0, 0) , (1, 1) , and (2, 2) for a sum of 1 + 5 + 9 = 15 .
Example 3
Input: board = [[1,1,1],[1,1,1],[1,1,1]]
Output: 3
Explanation:
We can place the rooks in the cells (0, 2) , (1, 1) , and (2, 0) for a sum of 1 + 1 + 1 = 3 .
Constraints
3 <= m == board.length <= 5003 <= n == board[i].length <= 500-109 <= board[i][j] <= 109
3257. Maximum Value Sum by Placing Three Rooks II
Hard
50 Points
Array
Dynamic Programming
Matrix
Enumeration
You are given a m x n 2D array board representing a chessboard, where board[i][j] represents the value of the cell (i, j).
Rooks in the same row or column attack each other. You need to place three rooks on the chessboard such that the rooks do not attack each other.
Return the maximum sum of the cell values on which the rooks are placed.
Examples
Example 1
Input: board = [[-3,1,1,1],[-3,1,-3,1],[-3,2,1,1]]
Output: 4
Explanation:
We can place the rooks in the cells (0, 2) , (1, 3) , and (2, 1) for a sum of 1 + 1 + 2 = 4 .
Example 2
Input: board = [[1,2,3],[4,5,6],[7,8,9]]
Output: 15
Explanation:
We can place the rooks in the cells (0, 0) , (1, 1) , and (2, 2) for a sum of 1 + 5 + 9 = 15 .
Example 3
Input: board = [[1,1,1],[1,1,1],[1,1,1]]
Output: 3
Explanation:
We can place the rooks in the cells (0, 2) , (1, 1) , and (2, 0) for a sum of 1 + 1 + 1 = 3 .
Constraints
3 <= m == board.length <= 5003 <= n == board[i].length <= 500-109 <= board[i][j] <= 109