3 人解决,13 人已尝试。
4 份提交通过,共有 59 份提交。
9.3 EMB 奖励。
单点时限: 2.0 sec
内存限制: 256 MB
A local high school is going to hold a final exam in a big classroom. However, some students in this school are always trying to see each other’s answer sheet during exams!
The classroom can be regarded as a rectangle of $M$ rows by $N$ columns of unit squares, where each unit square represents a seat.
The school principal decided to set the following rule to prevent cheating:
Assume a student is able to see his left, right, upper-left, and upper-right neighbors’ answer sheets. The assignment of seats must guarantee that nobody’s answer sheet can be seen by any other student.
As in this picture, it will not be a good idea to seat anyone in A, C, D, or E because the boy in the back row would be able to see their answer sheets. However, if there is a girl sitting in B, he will not be able to see her answer sheet.
Some seats in the classroom are broken, and we cannot put a student in a broken seat.
The principal asked you to answer the following question: What is the maximum number of students that can be placed in the classroom so that no one can cheat?
The first line of input gives the number of cases, $C$ $(C=20)$. $C$ test cases follow. Each case consists of two parts.
The first part is a single line with two integers $M$ $(1 \le M \le 80)$ and $N$ $(1 \le N \le 80)$: The height and width of the rectangular classroom.
The second part will be exactly $M$ lines, with exactly $N$ characters in each of these lines. Each character is either a .
(the seat is not broken) or x
(the seat is broken, lowercase x
).
For each test case, output one line containing Case #X: Y
, where X
is the case number, starting from $1$, and Y
is the maximum possible number of students that can take the exam in the classroom.
4 2 3 ... ... 2 3 x.x xxx 2 3 x.x x.x 10 10 ....x..... .......... .......... ..x....... .......... x...x.x... .........x ...x...... ........x. .x...x....
Case #1: 4 Case #2: 1 Case #3: 2 Case #4: 46
3 人解决,13 人已尝试。
4 份提交通过,共有 59 份提交。
9.3 EMB 奖励。