Python程式計算樹中葉子節點的數量
當需要計算樹中葉子節點的數量時,會建立一個名為“Tree_structure”的類,並定義新增根值和其他子值的方法。使用者可以選擇各種選項。根據使用者的選擇,對樹元素執行操作。
下面是相同的演示 -
示例
class Tree_structure: def __init__(self, data=None): self.key = data self.children = [] def set_root_node(self, data): self.key = data def add_vals(self, node): self.children.append(node) def search_val(self, key): if self.key == key: return self for child in self.children: temp = child.search(key) if temp is not None: return temp return None def count_leaf_node(self): leaf_nodes = [] self.count_leaf_node_helper_fun(leaf_nodes) return len(leaf_nodes) def count_leaf_node_helper_fun(self, leaf_nodes): if self.children == []: leaf_nodes.append(self) else: for child in self.children: child.count_leaf_node_helper_fun(leaf_nodes) tree = None print('Menu (this assumes no duplicate keys)') print('add <data> at root') print('add <data> below <data>') print('count') print('quit') while True: my_input = input('What operation would you like to perform ? ').split() operation = my_input[0].strip().lower() if operation == 'add': data = int(my_input[1]) newNode = Tree_structure(data) sub_op = my_input[2].strip().lower() if sub_op == 'at': tree = newNode elif sub_op == 'below': my_pos = my_input[3].strip().lower() key = int(my_pos) ref_node = None if tree is not None: ref_node = tree.search_val(key) if ref_node is None: print('No such key.') continue ref_node.add_vals(newNode) elif operation == 'count': if tree is None: print('The tree is empty') else: count = tree.count_leaf_node() print('The number of leaf nodes are : {}'.format(count)) elif operation == 'quit': break
輸出
Menu (this assumes no duplicate keys) add <data> at root add <data> below <data> count quit What operation would you like to perform ? add 78 at root What operation would you like to perform ? add 90 below 78 What operation would you like to perform ? add 8 below 78 What operation would you like to perform ? count The number of leaf nodes are : 2 What operation would you like to perform ? quit
解釋
建立“Tree_structure”類。
它將“key”設定為True,並將樹的子節點設定為一個空列表。
它有一個名為“set_root”的函式,用於設定樹的根值。
定義了一個名為“add_vals”的方法,用於向樹中新增元素。
定義了一個名為“search_val”的方法,用於在樹中搜索元素。
定義了一個名為“count_leaf_nodes”的方法,用於獲取樹中葉子節點的數量。
定義了一個名為“count_leaf_nodes_helper”的方法,它呼叫前面定義的函式 - 這是一個遞迴函式。
提供了四個選項,例如“新增到根節點”、“新增到下方”、“計數”和“退出”。
根據使用者提供的選項,執行相應的操作。
此輸出顯示在控制檯上。
廣告