DWITE Online Computer Programming Contest
October 2005

Problem 2

The Game of Life

The Game of Life is not a game in the conventional sense. There are no players, and no winning or losing. Once the "pieces" are placed in the starting position, the rules determine everything that happens later. Nevertheless, Life is full of surprises! In most cases, it is impossible to look at a starting position (or pattern) and see what will happen in the future. The only way to find out is to follow the rules of the game.

Rules of the Game of Life

Life is played on a grid of square cells - like a chess board but extending infinitely in every direction. A cell can be live or dead. A live cell is shown by putting a marker on its square. A dead cell is shown by leaving the square empty. Each cell in the grid has a neighborhood consisting of the eight cells in every direction including diagonals (except the cells along the border). To apply one step of the rules, we count the number of live neighbors for each cell. What happens next depends on this number.

• A dead cell with exactly three live neighbors becomes a live cell (birth).
• A live cell with two or three live neighbors stays alive (survival).
• A live cell, with four or more neighbors OR one or less neighbors, dies (overcrowding or loneliness).

Note: The number of live neighbors is always based on the cells before the rule was applied. In other words, we must first find all of the cells that change before changing any of them. Sounds like a job for a computer!

Input

The input will contain the information for the starting generation on the grid. The first line will contain two integers, r and c, that represent the number of rows and columns of the grid, respectfully, 3 ≤ r,c ≤ 50. The next r lines will contain c characters, either a "." (period), representing a dead cell, or an "X" representing a live cell.

Output

The output will contain five lines of data, each representing the number of live cells after the first, fifth, tenth, fiftieth and one hundredth generation, respectfully.

Sample Input

10 10
..XX..XXXX
.X.XX.XX..
XX....X..X
X...XX..XX
X..X.X....
..........
.XXX.....X
.......XXX
......XX..
X.X.X.X...

Sample Output

38
30
27
0
0

All Submissions
Best Solutions

Point Value: 10 (partial)
Time Limit: 1.00s
Memory Limit: 32M
Added: Mar 06, 2009

Languages Allowed:
C++03, PAS, C, HASK, ASM, RUBY, PYTH2, JAVA, PHP, SCM, CAML, PERL, C#, C++11, PYTH3

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