## TFRIENDS - True Friends

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You are given a string array representing Known people. Known[i][j]='Y' if i knows j.

Friends: A is a friend of B if B knows A or B has a friend who knows A.

True friends: A and B are true friends if A is a friend of B and B is a friend of A.

Group: Everyone in a Group must be true friends to each other.

Your task is to find the number of Groups from the given list of Known people. It can be proved that there is exactly only one possible way for forming the groups.

Input: The first line consists of an integer t, the number of test cases. For each test case, you are given an array of strings representing Known people. Known is of size NxN where N is the total number of people.

Output: For each test case, print the number of Groups.

Input Constraints:

1<=t<=1000

1<=N<=100

Known[i][j] is either 'Y' or 'N'

Known[i][i]='N' (No one is known to themselves)

Sample Input:

```3
3
NYN
NNY
YNN
7
NNYNNNN
NNNYYYN
NNNNNNN
YNNNNNN
NNNYNNN
NNNNNNN
NNNNNYN
7
NNNNYYN
NNNNNNN
NNNNNYN
NYNNNYY
NNNYNNN
NNYNNNY
NNNNYNN```

Sample Output:

```1
7
3```

Explanation:

Case 1: All the friends are true friends to each other

Case 2: No two true friends exist.

Case 3: There are 3 groups of true friends. {0}, {1}, {2,3,4,5,6}

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 < Previous 1 2 Next > kshubham02: 2019-08-19 19:11:16 I wonder if all of [spoiler], [spoiler]. and [spoiler] will get converted to [spoiler]s automatically. Last edit: 2019-09-30 14:36:14 shiv2111: 2018-01-16 16:03:29 simple [spoiler] Last edit: 2018-08-22 16:19:58 Simes: 2017-11-01 13:25:34 @gohanssj9: from reading the comments, it looks like you need to use the [spoiler] algorithm. (@cegprakash, I self-censored to save you the trouble!) Reply by author : Thank you! Last edit: 2018-08-22 16:20:41 gohanssj9: 2016-09-20 20:33:04 Hi,can anyone tell me how you people managed to get the execution time under 0.50sec? I mean,which algorithm should we use to get that kind of timing? Thank you. Vipul Srivastava: 2016-06-28 15:15:43 I am constantly getting WA, I have checked multiple test cases. @cegprakash can you please help? Last edit: 2016-06-28 15:15:56 princekumar: 2016-06-20 15:22:38 [spoiler question] ? Last edit: 2016-07-29 22:30:42 naruto09: 2016-01-29 01:15:08 the question shouts to implement the [spoiler] algorithm. Last edit: 2016-07-29 22:31:04 Arjav: 2016-01-24 22:14:20 [spoiler]....:) Last edit: 2016-07-29 22:31:17 varun yadav: 2015-11-04 11:57:19 Piece of cake,, without seeing any reference Last edit: 2015-11-04 11:57:52 thenamesake: 2015-10-08 12:47:07 Simply find the [spoiler removed] Last edit: 2015-10-12 14:19:29

 Added by: cegprakash Date: 2014-03-10 Time limit: 1s Source limit: 50000B Memory limit: 1536MB Cluster: Cube (Intel G860) Languages: All except: BF