Can the dog reach the neighbour's house?

Question

A dog is leashed to a pole and the owner wants to know if it can venture to the neighbour's building. You're given a map, which contains the pole (represented by x), the owner's buildings (represented by 1) and the neighbour's building (represented by 2). Empty areas are padded with dots and every line has the same length. EDIT: I forgot to mention, neighbour is always to the right from the dog. Every tile represents an area of one square meter. You're also given the length of the dog's leash (as meters). The pole is at the center of the tile. For input you must use the STDIN (and respectively STDOUT for output), if it's available in your language. Otherwise create a function, which takes the input as parameters and returns the answer. An example input to the STDIN would look like this.

6           
............
...11..222..
...11..222..
...11.......
.x.11.......
............

Additional newline is guaranteed after the input. The program should output Yes if the dog can reach the neighbour's building and otherwise No.

Assumptions

• There can be several buildings belonging to the owner.
• There can only be one neighbour's building.
• The dog can't venture outside the map or through the buildings.
• The dog can't be trapped inside a building.
• The length of the leash is always an integer
• Distances are calculated in Euclidean metric.

This is a codegolf, shortest code wins.

Test cases

Input:

6           
............
...11..222..
...11..222..
...11.......
.x.11.......
............

Output: No

Input:

7           
............
...11..222..
...11..222..
...11.......
.x.11.......
............

Output: Yes

Input:

7       
........
...11...
..111.22
..111.22
.x111.22
..111.22
..111...

Output: No

Input:

8       
........
...11...
..111.22
..111.22
.x111.22
..111.22
..111...

Output: Yes

Answer 1

PHP 781 chars

I know this can be smaller but I am sorry that I am confused. If I take your first two examples (answers no and yes), if diagonal moves are not allowed, answers should be no and no, surely. If diagonal moves are allowed, answers should be yes and yes. Have I misunderstood?

I also took beside to be the criteria of 'reached' as the dog can then wee on the building - however changing that to on top of can easily be done changing the pass counter which currently equals leash length.

Anyway, this allows for diagonal movement, non diagonal would be smaller than this.

<?php
$a.='7           
............
...11..222..
...11..222..
...11.......
.x.11.......
...........';$b='No';$c=array();$d=array();function check_2($e,$f){if(($c[$e+1][$f-1]=='2')OR($c[$e+1][$f]=='2')OR($c[$e+1][$f+1]=='2')OR($c[$e][$f-1]=='2')OR($c[$e][$f]=='2')OR($c[$e][$f+1]=='2')OR($c[$e-1][$f-1]=='2')OR($c[$e-1][$f]=='2')OR($c[$e-1][$f+1]=='2')){return TRUE;;}else{return FALSE;}}str_replace("\n\r","\n",$a);$g=explode("\n",$a);$h=$g[0];unset($g[0]);$i=count($g);$j=0;foreach($g as $k){$l=str_split($k);$m=count($l)+1;unset($l[$m]);$c[$j]=$l;++$j;}$d=$c;for($n=0;$n<=$h;++$n){for($e=0;$e<$i;++$e){for($f=0;$f<$m;++$f){if($c[$e][$f]=='2'){$b='Yes';}if($c[$e][$f]=='x'){for($o=-1;$o<2;++$o){for($p=-1;$p<2;++$p){if($c[$e+$o][$f+$p]=='.'){$d[$e+$o][$f+$p]='x';}}}}}}$c=$d;}echo $b;?>

I am pretty sure I can make this smaller but with the confusion not sure which way to go.

Anyway this is my first flood fill so I am sure it can be done more efficiently. Most of the work was getting the input into a variable and a multi dimensional array.

The input it contained in the first variable $a. You can see it here on codepad.

I hope you like it. As a relative newbie and since this is the only answer I suppose I am officially winning here at the moment. Although I cannot imagine this will last long if someone else enters :-)