Python data structures and algorithms--dictionary tree

1 classTrietree ():2     def __init__(self):3Self.root = {}4     5     defAddNode (SELF,STR):6         #each node (root node) in the tree that contains the number of words to that node, and the key that appears after the node.7Nowdict =Self.root8          forIinchRange (len (str)):9             ifStr[i] not inchNowdict:#discover new ways to combineTenNowdict[str[i]] = {'Count'70A'prefix': str[:i+1]} OneNowdict = Nowdict[str[i]]#move to the next node. Anowdict['Count'] + = 1 -      -     defCountword (SELF,STR): the         #returns the number of occurrences of the input word in the tree -Nowdict =Self.root -          forSinchStr: -             ifS not inchnowdict: +                 return0 -Nowdict = Nowdict[s]#match the current node and go to the next node . +         #This step proves the existence of the word A         returnnowdict['Count'] at  -  -  -  -  - if __name__=="__main__": in     Pass -Text = ['b','ABC','Abd','BCD','ABCD','EFG','hii','BCD'] tot =Trietree () +      forStrinchText: - T.addnode (str) the     PrintT.countword ('BCD') *  $>>> 2

Reference: http://blog.csdn.net/v_july_v/article/details/6897097

Python data structures and algorithms--dictionary tree