recursion

问题 How is a JUMP and CALL instruction different? How does it relate to the higher level concepts such as a GOTO or a procedure call? (Am I correct in the comparison?) This is what I think: JUMP or GOTO is a transfer of the control to another location and the control does not automatically return to the point from where it is called. On the other hand, a CALL or procedure/function call returns to the point from where it is called. Due to this difference in their nature, languages typically make

问题 Following is my array [ {id: 1, title: 'hello', parent: {number:0}}, {id: 2, title: 'hello', parent: {number:0}}, {id: 3, title: 'hello', parent: {number:1}}, {id: 4, title: 'hello', parent: {number:3}}, {id: 5, title: 'hello', parent: {number:4}}, {id: 6, title: 'hello', parent: {number:4}}, {id: 7, title: 'hello', parent: {number:3}}, {id: 8, title: 'hello', parent: {number:2}} ] and I want to have objects nested like this as output : [ {id: 1, title: 'hello', parent: 0, children: [ {id: 3,

问题 I have a dictionary looking like this: d ={'key1':{'key2':{'key11':{'key12':'value 13'}}},'key3':[{'key4':'value2', 'key5': 'value3'}]} I want to get the value for 'key12' so I can do this: d.get('key1').get('key2').get('key11').get('key12') and it will return this: 'value 13' if I had a list like this: ['key1', 'key2', 'key11', 'key12'] how could I call the get recursively over the above list to return the same result? 回答1: You can use functools.reduce: >>> from functools import reduce >>>

问题 I just know how to use for to draw a tree (the tree data is the picture one, the result is picture two), but now I want to use recursion to draw the tree. Please tell me how change writing style from for to recursive first input point //input point const line_point =[0, 0, 0, 2, 151, 2, 2, 151, 2, -62, 283, 63, 2, 151, 2, 62, 297, -58, -62, 283, 63, -104, 334, 74, -62, 283, 63, -58, 338, 45, 62, 297, -58, 67, 403, -55, 62, 297, -58, 105, 365, -86]; take out star point and end point const star

问题 Given a dataframe as follows: root subroot leaf value 0 A B1 C1 58 1 A B1 C2 7 2 A B2 C1 0 3 A B2 C2 20 and code as follows: from collections import deque class Node: def __init__(self, name, weight, children): self.name = name self.children = children self.weight = weight self.weight_plus_children = weight def get_all_weight(self): if self.children is None: return self.weight_plus_children for child in self.children: self.weight_plus_children += child.get_all_weight() return self.weight_plus

问题 Given a dataframe as follows: root subroot leaf value 0 A B1 C1 58 1 A B1 C2 7 2 A B2 C1 0 3 A B2 C2 20 and code as follows: from collections import deque class Node: def __init__(self, name, weight, children): self.name = name self.children = children self.weight = weight self.weight_plus_children = weight def get_all_weight(self): if self.children is None: return self.weight_plus_children for child in self.children: self.weight_plus_children += child.get_all_weight() return self.weight_plus

问题 I have found the code from this link: class Node: def __init__(self, name, weight, children): self.children = children self.weight = weight self.weight_plus_children = weight def get_all_weight(self): if self.children is None: return self.weight_plus_children else: for child in self.children: print("child.get_all_weight()", child.get_weigth_with_children()) self.weight_plus_children += child.get_weigth_with_children() return self.weight_plus_children def get_weigth_with_children(self): return

问题 I was running a recursive file search procedure, and my computer shut down. I know what directory the procedure stopped at, is there a way I can specify a start folder for a recursive file search? For example, let's say this is my structure R:\ R:\Test\ R:\Test\Folder1\ R:\Test1\ R:\Test1\Folder1\ R:\Test2\ R:\Test2\Folder2\ if I wanted the recursive search to start at R:\Test1\Folder1\ how would the procedure go? Option Compare Database Sub ScanTablesWriteDataToText() Dim Fileout As Object

问题 I am quite confused with the code below. def a(x): print(x) if x > 0: a(x - 1) print(x) #I am confused with this print statement a(5) The above code outputs: 5 4 3 2 1 0 0 1 2 3 4 5 Up till the 0 I understand how it prints, but then why it prints in ascending order . Variable x is changing so what I thought the output would be is the last assigned value of x that is 0 . My predicted output: 5 4 3 2 1 0 0 0 0 0 0 0 So how does it track the value of x...? Can someone explain in brief what

问题 Closed . This question is opinion-based. It is not currently accepting answers. Want to improve this question? Update the question so it can be answered with facts and citations by editing this post. Closed 3 years ago . Improve this question I always thought things that make your code uneasy to follow while being avoidable are considered as Bad Practice. Recursion seems to be one of these things (not to mention the problems it can cause like stack overflowing etc.), so I was a bit surprised