KATHTHI  KATHTHI
Kathiresan is initially locked at cell (0,0) in a highly guarded rectangular prison of order RxC. He must reach the gate at (R1,C1) in order to escape from the prison. Kathiresan can move from any cell, to any of it's 4 adjacent cells (North, East, West and South). If Kathiresan is currently at (x1,y1), then he can move to (x2,y2) if and only if abs(x2x1)+abs(y2y1) == 1 and 0<=x2<R and 0<=y2<C
Kathiresan somehow manages to get the map of the prison.
If map[x1][y1] == map[x2][y2] then Kathiresan can move from (x1,y1) to (x2,y2) without killing any guards.
If map[x1][y1] != map[x2][y2], then Kathiresan can move from (x1,y1) to (x2,y2) by killing a guard.
Given the map of the prison, find the minimum number of guards Kathiresan must kill in order to escape from the prison.
Input:
The first line consists of an integer t, the number of test cases. For each test case, the first line consists of two integers R and C representing the order of the rectangular prison followed by R strings representing the map of the rectangular prison.
Output:
For each test case find the minimum number of guards Kathiresan must kill in order to escape from the prison.
Input Constraints:
1 <= t <= 10
2 <= R <= 1000
2 <= C <= 1000
'a' <= map[i][j] <= 'z'
Sample Input:
4
2 2
aa
aa
2 3
abc
def
6 6
akaccc
aaacfc
amdfcc
aokhdd
zyxwdp
zyxwdd
5 5
abbbc
abacc
aaacc
aefci
cdgdd
Sample Output:
0
3
2
2
hide comments
anirudnits:
20180813 17:46:25
[spoiler] does the trick! Last edit: 20180822 15:44:51 

anurag_tangri:
20180206 15:02:09
the last case is incorrect ! answer must be 3 . i dont understand how answer is 2?


shubiks:
20180123 21:52:20
don't do [spoiler], learn [spoiler] Last edit: 20180822 15:45:14 

nuhash_40:
20180117 15:07:46
USED [spoiler] AC in first attempt Last edit: 20180822 15:45:35 

sas1905:
20170618 20:41:49
Learnt something new in order to reduce TLE.!! 

gboduljak:
20170413 23:47:42
fastio not required, hint [spoiler] Last edit: 20170802 13:15:12 

vengatesh15:
20170212 20:25:33
AC after 6 TLE and learnt something new.. 

mkfeuhrer:
20161116 22:56:00
<Spoiler removed> and implement :) AC one go :) fast IO too! Last edit: 20161127 03:56:41 

Abhishek Jaisingh:
20160617 23:37:03
fastIO + [Spoiler removed] = AC!! Last edit: 20160729 21:53:30 

Keshav Reddy:
20151226 20:50:51
cin will give TLE in C++. 
Added by:  cegprakash 
Date:  20150116 
Time limit:  1s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All except: BF 