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':


One such path is:



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.


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


Sample Input:
4 3
0 0

Sample Output:
Case 1: 4

hide comments
gs959_me: 2019-04-04 15:22:46

AC in one go

Last edit: 2019-04-04 15:57:12
srthere: 2019-01-31 04:41:53

Last edit: 2019-02-04 13:33:11
me_milan_11: 2019-01-14 09:11:03

Didn't use memo and got 2 TLEs. Then AC

gaurav1614: 2018-12-26 18:08:22

DP on graphs.easily solvable in O(n*m) complexity.

manishjoshi394: 2018-11-05 16:50:43

Simple DFS, AC in one go! :)

joe85123: 2018-10-21 09:08:18

BFS and DFS both work just fine! good problem to practice both

masterchef2209: 2018-10-11 20:38:04

recursion +memoisation

ameyanator: 2018-09-16 08:29:43

Nice question I started with recursion and optimized it to multisource bfs. Got a lot of TLEs in between

nour_b3: 2018-09-09 19:30:29

AC in one go !!

c0der_ace: 2018-07-05 15:23:11

Simple DFS !! Just make once used characters unusable for further times as they can never help to reach farther than they did last time ;)

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