Problem Statement 
 There are N cities numbered 0 to N1. The jth character of the ith element of roads is 'Y' if there is a bidirectional road between cities i and j, and 'N' otherwise.
The road connecting cities A and B, where A < B, has a higher priority than the road connecting cities C and D, where C < D, if either A < C or (A = C and B < D). A set of roads is a list of one or more roads sorted from highest to lowest priority. A set S1 has a higher priority than set S2 if road S1[i] has a higher priority than road S2[i], where i is the earliest index at which the two sets differ. A set of roads is called connected if there's a path between any pair of cities containing only the roads from this set.
Your task is to find the connected set with the highest priority containing exactly M roads. Return a int[] where the ith element is the number of roads in that set containing city i as an endpoint. Return an empty int[] if there is no such set.


Definition 
 Class:  BestRoads  Method:  numberOfRoads  Parameters:  String[], int  Returns:  int[]  Method signature:  int[] numberOfRoads(String[] roads, int M)  (be sure your method is public) 




Constraints 
  roads will contain between 1 and 50 elements, inclusive.

  M will be between N1 and 1,000, inclusive, where N is the number of elements in roads.

  Each element of roads will contain exactly N characters 'Y' or 'N', where N is the number of elements in roads.

  For each i and j roads[i][j] will be equal to roads[j][i].

  For each i roads[i][i] will be equal to 'N'.


Examples 
0)  
 {"NYYYY","YNYYY","YYNYY","YYYNY","YYYYN"}  10 
 Returns: {4, 4, 4, 4, 4 }  All roads should be selected. 


1)  
  Returns: {2, 1, 1 }  The set must contain roads 01 and 02. 


2)  
 {"NYNNY","YNNNY","NNNNN","NNNNY","YYNYN"}  4 
 Returns: { }  City 2 can not be connected to others. 


3)  
 {"NYYNYYYN","YNNNNYYN","YNNNYNNN","NNNNNNYY","YNYNNNNN","YYNNNNYY","YYNYNYNY","NNNYNYYN"}  10 
 Returns: {5, 3, 2, 2, 2, 2, 3, 1 }  

4)  
 {"NNYY","NNYY","YYNN","YYNN"}  5 
 Returns: { }  There are totally 4 roads, so we can't choose 5 of them. 

