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.
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)
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
要小心它的输入
行列是相反的
坑在这里找了好多次TAT
#include<stdio.h>
#include<iostream>
using namespace std;
char map[][];
int n,m;
int num;
int rx[]={,,,-};
int ry[]={,-,,};
void dfs(int i,int j)
{
map[i][j]='#';
num++;
int t,x,y;
for(t=;t<;t++)
{
x=i+rx[t];
y=j+ry[t];
if(x>= && x<n && y>= && y<m && map[x][y]=='.')
dfs(x,y);
}
}
int main()
{
int i,j;
int si,sj;
while(scanf("%d%d",&m,&n)!=EOF)//原来是行数和列数反了...我真是醉了....
{ if(m==&&n==)break;
for(i=;i<n;i++)
for(j=;j<m;j++)
{
cin>>map[i][j];
if(map[i][j]=='@')
{
si=i;
sj=j;
}
}
num=;
dfs(si,sj);
printf("%d\n",num);
}
return ;
}