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On a 0-indexed 8 x 8 chessboard, there can be multiple black queens and one white king.

You are given a 2D integer array queens where queens[i] = [xQueeni, yQueeni] represents the position of the ith black queen on the chessboard. You are also given an integer array king of length 2 where king = [xKing, yKing] represents the position of the white king.

Return the coordinates of the black queens that can directly attack the king. You may return the answer in any order.

Example 1:

Input: queens = [[0,1],[1,0],[4,0],[0,4],[3,3],[2,4]], king = [0,0]
Output: [[0,1],[1,0],[3,3]]
Explanation: The diagram above shows the three queens that can directly attack the king.

1def queensAttacktheKing(queens: List[List[int]], king: List[int]) -> List[List[int]]:

2 result = []

3 queens_set = {(r, c) for r, c in queens}

4 # 8 directions: up, down, left, right, diagonals

5 directions = [

6 (-1, -1), (-1, 0), (-1, 1),

7 (0, -1), (0, 1),

8 (1, -1), (1, 0), (1, 1)

9 ]

11 for dr, dc in directions:

12 r, c = king

13 # Move in the current direction until we find a queen or hit the edge

14 while True:

15 r += dr

16 c += dc

17 if not (0 <= r < 8 and 0 <= c < 8):

18 break # Out of bounds

19 if (r, c) in queens_set:

20 result.append([r, c])

21 break # Found the first queen in this direction

23 return result

Queens That Can Attack the King

Reference solution