1488 - Rooks
Time Limit : 2 Second
Memory Limit : 128 MB
Submission: 4
Solved: 3
- Description
- You have unexpectedly become the owner of a large chessboard, having fifteen squares to each side. Because you do not know how to play chess on such a large board, you find an alternative way to make use of it.
In chess, a rook attacks all squares that are in the same row or column of the chessboard as it is. For the purposes of this problem, we define a rook as also attacking the square on which it is already standing.
Given a set of chessboard squares, how many rooks are needed to attack all of them? - Input
- Input consists of a number of test cases. Each test case consists of fifteen lines each containing fifteen characters depicting the chess board. Each character is either a period (.) or a hash (#). Every chessboard square depicted by a hash must be attacked by a rook. After all the test cases, one more line of input appears. This line contains the word END.
- Output
- Output consists of exactly one line for each test case. The line contains a single integer, the minimum number of rooks that must be placed on the chess board so that every square marked with a hash is attacked.
- sample input
-
............... ............... ............... ............... ............... ............... ............... .......#....... ............... ............... ............... ............... ............... ............... ............... END
- sample output
-
1
- hint
- source
- waterloo 3 October, 2009