ABCPATH - ABC Path

no tags 

You will be given a 2-dimensional grid of letters. Find the length of the longest path of consecutive letters, starting at 'A'. Paths can step from one letter in the grid to any adjacent letter (horizontally, vertically, or diagonally).

For example, in the following grid, there are several paths from 'A' to 'D', but none from 'A' to 'E':

ABC

One such path is:

path

Input

Each test case will start with a line contains two integers H, W the height and width of the grid respectively 1 <= H, W <= 50. Then H lines follow each of W uppercase letters only. Input terminates with H = 0 and W = 0.

Output

For each test case print “Case C: X” without quotes where C is the case number starting with 1 and X is the solution.

Example

Sample Input:
4 3
ABE
CFG
BDH
ABC
0 0

Sample Output:
Case 1: 4

hide comments
Hasil Sharma: 2014-01-16 08:57:50

Initial image is missing ... Can anyone please provide the link ?

Ouditchya Sinha: 2013-06-08 11:20:08

Nice problem. :)

god_father: 2013-01-26 09:47:13

nice question...be carefull about visited paths it caused me 2 TLE;

cegprakash: 2011-11-15 05:46:57

is A to B, B to C, C to B, B to C, C to D is a valid path?

edited by Ali: No! the path must involve the letter once , the letters should be consecutive and the path starts with 'A'

Last edit: 2011-11-16 23:12:37
Ali Arous: 2011-11-06 09:35:49

No, the Longest path is from "A" to "Z"

[Retired] Fendy Kosnatha: 2011-11-06 04:22:22

if after 'Z' can be back to 'A'??


Added by:Ali Arous
Date:2011-11-05
Time limit:1s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ASM64
Resource:FCIS Local Contest 2012