Red and Black
Time Limit:1000MSMemory Limit:30000K
Total Submissions:25797Accepted:13967
Description
There is a rectangular room, covered with square tiles. Each tile is colored either red or black. A man is standing on a black tile. From a tile, he can move to one of four adjacent tiles. But he can’t move on red tiles, he can move only on black tiles.Write a program to count the number of black tiles which he can reach by repeating the moves described above.
Input
The input consists of multiple data sets. A data set starts with a line containing two positive integers W and H; W and H are the numbers of tiles in the x- and y- directions, respectively. W and H are not more than 20.There are H more lines in the data set, each of which includes W characters. Each character represents the color of a tile as follows.’.’ – a black tile’#’ – a red tile’@’ – a man on a black tile(appears exactly once in a data set)The end of the input is indicated by a line consisting of two zeros.
Output
For each data set, your program should output a line which contains the number of tiles he can reach from the initial tile (including itself).
Sample Input
6 9….#……#…………………………#@…#.#..#.11 9.#……….#.#######..#.#…..#..#.#.###.#..#.#..@#.#..#.#####.#..#…….#..#########…………11 6..#..#..#….#..#..#….#..#..###..#..#..#@…#..#..#….#..#..#..7 7..#.#….#.#..###.###…@…###.###..#.#….#.#..0 0
Sample Output
4559613
Source
，如果心胸不似海，又怎能有海一样的事业。
