Class Solution
java.lang.Object
g0401_0500.s0419_battleships_in_a_board.Solution
public class Solution
extends java.lang.Object
419 - Battleships in a Board.
Medium
Given an m x n
matrix board
where each cell is a battleship 'X'
or empty '.'
, return the number of the battleships on board
.
Battleships can only be placed horizontally or vertically on board
. In other words, they can only be made of the shape 1 x k
(1
row, k
columns) or k x 1
(k
rows, 1
column), where k
can be of any size. At least one horizontal or vertical cell separates between two battleships (i.e., there are no adjacent battleships).
Example 1:
Input: board = [[“X”,“.”,“.”,“X”],[“.”,“.”,“.”,“X”],[“.”,“.”,“.”,“X”]]
Output: 2
Example 2:
Input: board = [[“.”]]
Output: 0
Constraints:
m == board.length
n == board[i].length
1 <= m, n <= 200
board[i][j]
is either'.'
or'X'
.
Follow up: Could you do it in one-pass, using only O(1)
extra memory and without modifying the values board
?
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Constructor Summary
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Method Summary
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
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Constructor Details
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Solution
public Solution()
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Method Details
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countBattleships
public int countBattleships(char[][] board)
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