sorting

问题 Code: import math import time import random class SortClass(object): def sort1(self, l): if len(l)==1: return l elif len(l)==2: if l[0]<l[1]: return l else: return l[::-1] else: pivot=math.floor(len(l)/2) a=l[pivot:] b=l[:pivot] a2=self.sort1(a) b2=self.sort1(b) if a2==None or b2==None: a2=[] b2=[] return (a2+b2).sort() return [] Sort=SortClass() x=[20,19,18,17,16,15,14,13,12,11,10,9,8,7,6,5,4,3,2,1] print(Sort.sort1(x)) The code outputs None even though it should return an empty list in two

问题 I am new to iphone development and need some guidance to do custom sorting of an array in iOS. I would like to sort the objects that appear in the UIPickerView. The objects that are passed to the UIPickerView are in an array. When I print the array out, it looks like this: "<ObjectsInfo: 0x1c5249f0>", "<ObjectsInfo: 0x1c524940>", "<ObjectsInfo: 0x1c5248e0>", "<ObjectsInfo: 0x1c524890>", "<ObjectsInfo: 0x1c524840>", "<ObjectsInfo: 0x1c524a90>", When i print out the first object's name:

问题 I have 5 different arrays that have the same index, eg: person[0]="john", address[0]= "Druid Valley", city[0]="Atlanta", amount[0]=2000, need[0]=100; person[1]="emily", address[1]="50 decatur", city[1]="Chicago", amount[1]=300; need[1]=50; I need to reorder all arrays in the descending order of the need[] array then re-arrange the order of the other arrays based on new index for need[i]. I'm using javascript. Thank you, John 回答1: Sort the need array and save the sort permutation, then apply

问题 I was wondering if my line of thinking is correct. I'm preparing for interviews (as a college student) and one of the questions I came across was to find the K largest numbers in an array. My first thought was to just use a partial selection sort (e.g. scan the array from the first element and keep two variables for the lowest element seen and its index and swap with that index at the end of the array and continue doing so until we've swapped K elements and return a copy of the first K

问题 I'm looking for an accordion table which can be sorted and paged. I couldn't find any sort/page plugin which would allow my table to have an accordion effect. In order to get the accordion effect, and to group each row for manipulation, I used multiple tbody tags. <tbody> <tr> <td>1</td> <td>Zulu</td> <td>Raleigh</td> <td>North Carolina</td> </tr> <tr class="collapse"> <td colspan="4">...hidden panel...</td> </tr> </tbody> <tbody> <tr> <td>2</td> <td>Yankee</td> <td>Detroit</td> <td>Michigan<

问题 I wonder if this is possible in oracle to replace row number (we can use ROW_NUMBER() for example to get a digit) into alfabetical numbering Let's say to get something like NO | Name | Surname ================ A | John | Doe B | Will | Doe C | Jim | Wonder instead of NO | Name | Surname | ================= 1 | John | Doe 2 | Will | Doe 3 | Jim | Wonder I have an idea to create a variable like "ABCDEFG" and convert row number into correct SUBSTR , but this sounds a little unstable Temporary

问题 I need to show 1000 test questions to a student, 10 per page. The questions are in a mysql table, the answers will go in another table. I need each students questions to appear in a different predetermined order than any other students. The sort order is predetermined when they register and placed in a usermeta table. In the usermeta table there is a column that lists the order in which the questions should be shown. The order in that column is unique to each student and looks like this

问题 Can anyone explain me this sentence please? The sorting algorithm is a modified mergesort (in which the merge is omitted if the highest element in the low sublist is less than the lowest element in the high sublist). Link: Arrays.sort(Object[] arr) I know how Merge works, but I still don't understand well. Thank you. 回答1: Mergesort recursively merges sorted sublists. If the current sublists eligible for merging contain no overlapping elements, there's no need to merge them. The merge

问题 Can anyone explain me this sentence please? The sorting algorithm is a modified mergesort (in which the merge is omitted if the highest element in the low sublist is less than the lowest element in the high sublist). Link: Arrays.sort(Object[] arr) I know how Merge works, but I still don't understand well. Thank you. 回答1: Mergesort recursively merges sorted sublists. If the current sublists eligible for merging contain no overlapping elements, there's no need to merge them. The merge

问题 I have a heap made of a binary tree. Its not an array. I was wondering how would i go about sorting this. I know i need to take the last node and place it at the root and do a down heap bubble. This part i have. The problem I am having is knowing how to get the new last node. Is there an algorithm to find the last node? Do i need to keep track of each of the parent nodes on each node? Thanks. 回答1: Assuming the tree you start with is a full tree, I would see if you can keep track of the height