ACM 2011 - Holey cloth

Problem L. Holey cloth ≡

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Author:	Far-Eastern Subregional	Time limit:	1 sec
Input file:	input.txt	Memory limit:	8 Mb
Output file:	output.txt

Statement

Several pieces of cloth are laid out on the table without overlapping each other. These pieces contain many holes, some so big that entire other piece of cloth may fit into them. Digital black-and-white image of the tabletop was taken, on which areas covered by cloth are represented with '*'s and not covered areas with '.'s. A single piece of cloth is thus represented with 4-connected area of '*'s - i.e., a group of '.'s located next to each other horizontally or vertically, but not diagonally. For example, on the following image there are three pieces - one without holes, and two with one hole each - first has area of 8, and the second - area of 12.

.***..***
.*.*.**.*
.***.*.**
*...**.*.

Your goal is to find the piece with the most holes in it. The hole is a 4- connected area of '.'s completely surrounded with '*'s. If several pieces have the same number of holes, you must select the one with the smallest area.

Input file format

In the first line of input file there are two numbers W and H, separated by spaces. Next H lines contain W characters each. Characters in these lines are either '*' (ASCII 42) or '.' (ASCII 46).

Output file format

The output file must contain a single integer - the area of the smallest of most holey pieces. If there are no pieces with the holes, the output file must contain zero.

Constraints

1 ≤ W, H ≤ 100

Sample tests

No.	Input file (`input.txt`)	Output file (`output.txt`)
1	`9 5 .******** ....... ..... ....... .********`	`22`