【HDOJ】2414 Chessboard Dance

简单DFS。

 /* 2414 */
 #include <cstdio>
 #include <cstring>
 #include <cstdlib>

 const int n = ;
 char map[][];
 int x, y, d;
 char dirs[] = "^v<>";
 int dir[][] = {
     -,, ,, ,-, ,
 };
 int tdir[][] = {
     ,,, ,,, ,,, ,,
 };

 inline bool check(int x, int y) {
     return x< || x>=n || y< || y>=n;
 }

 void dfs(int x, int y) {
     int i, j, k;
     int xx, yy;

     xx = x + dir[d][];
     yy = y + dir[d][];
     if (check(xx, yy))
         return ;
     if (map[xx][yy] == '.') {
         map[xx][yy] = map[x][y];
         map[x][y] = '.';
     } else {
         dfs(xx, yy);
         map[xx][yy] = map[x][y];
         map[x][y] = '.';
     }
 }

 int main() {
     int i, j, k;
     char cmd[];
     int xx, yy;

     #ifndef ONLINE_JUDGE
         freopen("data.in", "r", stdin);
         freopen("data.out", "w", stdout);
     #endif

     while (scanf("%s", map[]) != EOF) {
         if (map[][]=='-' && map[][]=='-' && map[][]=='\0')
             break;
         for (i=; i<; ++i)
             scanf("%s", map[i]);
         for (i=; i<; ++i) {
             for (j=; j<; ++j) {
                 if (map[i][j] == '^') {
                     x = i;
                     y = j;
                     d = ;
                 } else if (map[i][j] == 'v') {
                     x = i;
                     y = j;
                     d = ;
                 } else if (map[i][j] == '<') {
                     x = i;
                     y = j;
                     d = ;
                 } else if (map[i][j] == '>') {
                     x = i;
                     y = j;
                     d = ;
                 }
             }
         }
         while (scanf("%s", cmd)!=EOF && cmd[]!='#') {
             if (cmd[] == 'm') {
                 // move
                 scanf("%d", &k);
                 while (k--) {
                     xx = x + dir[d][];
                     yy = y + dir[d][];
                     if (check(xx, yy))
                         break;
                     dfs(x, y);
                     x = xx;
                     y = yy;
                 }
             } else {
                 // turn
                 scanf("%s", cmd);
                 if (cmd[] == 'l') {
                     d = tdir[d][];
                 } else if (cmd[] == 'r') {
                     d = tdir[d][];
                 } else {
                     d = tdir[d][];
                 }
             }
         }
         map[x][y] = dirs[d];
         for (i=; i<; ++i) {
             map[i][] = '\0';
             puts(map[i]);
         }
         putchar('\n');
     }

     return ;
 }