A board on the meter garlic guest of history (BFS) can't all through the bosses don't know where the problem o see

 
The class Node (object) : 
Def __init__ (self, x, y, c) : 
Self. X=x 
The self. The y=y 
C=c 
 of the self.Def BFS () : 
Color=1 
Color_x=None 
Color_y=None 
The queue=[[map_s [0] [0], 0]] 
Seen=[[0, 0]] 
While the queue: 
Try: 
Now=queue. Pop (0) 
Except BaseException: 
The return - 1 
If now [0]. X==m - 1 and now [0]==y m - 1: 
Return now [1] 
# determine whether can use magic 
If now [0]. X!=color_x and now [0]. Y!=color_y: 
Color=1 
Look_list=[] 
# whether except through the point of all empty 
For I in range (4) : 
Lin_tx=now [0]. X + dis [I] [0] 
Lin_ty=now [0]. Y + dis [I] [1] 
If lin_tx & gt;=0 and lin_tx & lt; M and lin_ty & gt;=0 and lin_ty & lt; M and [lin_tx lin_ty] not seen in: 
Look_list. Append (map_s [lin_tx] [lin_ty]. C) 
For I in range (4) : 
Tx=now [0]. X + dis [I] [0] 
Ty=now [0]. Y + dis [I] [1] 
If not 0 in look_list and 1 not in look_list: 
If tx>=0 and tx=0 and tySeen. Append ([the tx and ty]) 
Map_s [tx] [ty]. X=tx 
Map_s [tx] [ty] y=ty 
Map_s [tx] [ty]. C=now [0]. C 
Queue. Insert (0, [map_s [tx] [ty], now [1] + 2]) 
Color_x=tx 
Color_y=ty 
Color=0 
If tx>=0 and tx=0 and tySeen. Append ([the tx and ty]) 
If map_s [tx] [ty]. C==now [0]. C: 
Queue. Append ([map_s [tx] [ty], now [1]]) 
Elif map_s [tx] [ty]!=now [0]. C: 
Queue. Append ([map_s [tx] [ty], now [1] + 1]) 

The return - 1 

If __name__=="__main__" : 
M, n=map (int, input (). The split ()) 
Map_s=[[Node (None, None, None) for I in range (m)] for I in range (m)] 
For I in range (n) : 
Xx, yy, cc=map (int, input (). The split ()) 
Map_s xx - [1] [r]. Yy - 1 x=xx - 1 
Map_s xx - [1] [r]. Yy - 1 y=yy - 1 
Map_s xx - [1] [r]. Yy - 1 c=cc 
Dis=[[0, 1], [0, 1], [- 1, 0], [1, 0]] 
Ans=BFS () 
If ans!=1: 
Print (ans) 
The else: 
Print (1)