Red and Black
| Time Limit: 1000MS | Memory Limit: 30000K | |
| Total Submissions: 29990 | Accepted: 16293 |
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 深搜要多练练。
#include#include #include #include #include #include using namespace std;typedef long long LL;int m,n;char graph[25][25];bool vis[25][25];int sx,sy,cnt;int dir[][2] = { { 1,0},{-1,0},{ 0,1},{ 0,-1}};void dfs(int x,int y){ vis[x][y] = true; cnt++; for(int i=0; i<4; i++) { int nextx = x+dir[i][0]; int nexty = y+dir[i][1]; if(nextx<0||nextx>=n||nexty<0||nexty>=m||vis[nextx][nexty]||graph[nextx][nexty]=='#') continue; dfs(nextx,nexty); } return ;}int main(){ while(scanf("%d%d",&m,&n)!=EOF&&n+m) { cnt = 0; for(int i=0; i