Red and Black
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 5175 Accepted Submission(s): 3370
Problem 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.
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)
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)
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
45 59 6 13
#include <iostream> #include <cstring> using namespace std; #pragma warning(disable : 4996) #define MAX 25 char maps[MAX][MAX]; int w, h, ans; const int moves[4][2] = {{0, -1}, {0, 1}, {1, 0}, {-1, 0}}; void dfs(int x, int y) { maps[x][y] = '#'; for(int i = 0; i < 4; i++) { int p = x + moves[i][0]; int q = y + moves[i][1]; if(p >= 1 && p <= h && q >= 1 && q <= w && maps[p][q] == '.') { maps[p][q] = '#'; ans++; dfs(p, q); } } } int main() { freopen("in.txt", "r", stdin); int x, y; while (cin >>w >> h) { if(w == 0 && h == 0) { break; } for(int i = 1; i <= h; i++) { for(int j = 1; j <= w; j++) { cin >> maps[i][j]; if(maps[i][j] == '@') { x = i; y = j; } } } ans = 1; dfs(x, y); cout << ans << endl; } return 0; }