二叉木の構造及び各種遍歴

class Node(object):
    '''  '''
    def __init__(self,elem):
        self.data = elem
        self.lchild = None
        self.rchild = None

class Tree(object):
    '''   '''
    def __init__(self):
        self.root = None

    def add(self,item):
        node = Node(item)
        queue = []
        if self.root is None:
            self.root = node
            return
        queue.append(self.root)
        while queue:
            cur_node = queue.pop(0)
            if cur_node.lchild is None:
                cur_node.lchild = node
                return
            else:
                queue.append(cur_node.lchild)
            if cur_node.rchild is None:
                cur_node.rchild = node
                return
            else:
                queue.append(cur_node.rchild)
    def breath_traval(self):
        '''      '''
        if self.root is None:
            return
        queue = [self.root]
        while queue:
            cur_node = queue.pop(0)
            print(cur_node.data,end=' ')
            if cur_node.lchild is not None:
                queue.append(cur_node.lchild)
            if cur_node.rchild is not None:
                queue.append(cur_node.rchild)

    def pre_order(self,node):
        '''    '''
        if node is None:
            return
        print(node.data,end=' ')
        self.pre_order(node.lchild)
        self.pre_order(node.rchild)

    def mid_order(self,node):
        '''    '''
        if node is None:
            return
        self.mid_order(node.lchild)
        print(node.data, end=' ')
        self.mid_order(node.rchild)

    def post_order(self,node):
        '''    '''
        if node is None:
            return
        self.post_order(node.lchild)
        self.post_order(node.rchild)
        print(node.data, end=' ')

if __name__ == '__main__':
    tree = Tree()
    tree.add(1)
    tree.add(2)
    tree.add(3)
    tree.add(4)
    tree.add(5)
    tree.breath_traval()
    print('
')
    tree.pre_order(tree.root)
    print('
')
    tree.mid_order(tree.root)
    print('
')
    tree.post_order(tree.root)