#include <iostream>
#include <cstdio>
#include <cmath>
const int maxn = 10;
using namespace std;
bool escape;
char map[maxn][maxn];
int dir[4][2] = {{-1,0}, {1,0}, {0,-1}, {0,1}};
int n, m, t;
int si, sj, di, dj;
void dfs( int x, int y, int cnt )
{
if( escape ) return;
if( x == di && y == dj && cnt == t )
{
escape = 1;
return;
}
int temp = t - cnt - ( fabs(di - x) + fabs(dj - y ) );
if( temp < 0 || temp % 2 != 0 ) return;//奇偶剪枝
if( x <= 0 || y <= 0 || x > n || y > m ) return;
for( int i = 0; i < 4; i++ )
{
if( map[x+dir[i][0]][y+dir[i][1]] != 'X')
{
map[x+dir[i][0]][y+dir[i][1]] = 'X';
dfs(x+dir[i][0], y+dir[i][1], cnt+1);
map[x+dir[i][0]][y+dir[i][1]] = '.';
}
}
}
int main()
{
while( cin >> n >> m >> t, m || n || t )
{
int wall = 0;
escape = 0;
for ( int i = 1; i <= n; i++ )
for ( int j = 1; j <= m; j++ )
{
cin >> map[i][j];
if( map[i][j] == 'D')
{
di = i;
dj = j;
}
else if ( map[i][j] == 'S' )
{
si = i;
sj = j;
}
else if ( map[i][j] == 'X' )
wall ++ ;
}
if( m * n - wall <= t )
{
printf("NO\n");
continue;
}
else
{
map[si][sj] = 'X';
dfs( si, sj, 0 );
printf("%s\n", escape ? "YES" : "NO" );
}
}
return 0;
}
posted on 2010-07-29 06:58
Vontroy 閱讀(227)
評論(0) 編輯 收藏 引用 所屬分類:
搜索 、
HDU