insertion-sort

问题 A simple piece of code written by me: <?php function testing($a,$b){ if ($a < $b ){ return -1; } elseif ($a > $b){ return 1; } //else { //return 0; //} } $array = array(1,3,2,4,5); usort($array, "testing"); var_dump($array); ?> This is from the top comment (highest rated comment and from 5 years ago) on the php.net manual's usort page: "If you return -1 that moves the $b variable down the array, return 1 moves $b up the array and return 0 keeps $b in the same place." As far as I was looking

问题 Do these sorting algorithms have any use in real world application? Or is it just a basic example of sorting algorithm with n^2 complexity? Can anyone give some example of its usage? 回答1: Insertion sort is one of the fastest sorting algorithm for sorting very small arrays. In practice, many quicksort / mergesort implementations stop when the subarrays to sort is below certain threshold, and insertion sort is then used for these small arrays. Selection sort is rarely used in practice. 回答2:

问题 I am new in Dafny and getting some errors that I can not figure it out. in my Dafny program for insertionSort (the code is here), I do not understand why I get an invalid logical expression on While loop over variable i . while (i < |input|) in the same code at the swapping part ( input[j := b]; input[j-1 := a]; ) also I get expected method call, found expression . According to the tutorial input[j:=b] is replacing index j of seq input with the value of b 回答1: The first error is because you

问题 I was reading in Bentley & McIlroy (1993) that their suggested implementation of Quicksort uses Insertion Sort when the arrays get small enough. I was curious to know whether modern-day kernels use this same maneuver. Does anyone know whether the Linux kernel, for instance, switches from Quicksort to Insertion Sort in this way? 回答1: Assuming you mean the qsort from the C library, here's the qsort() from a somewhat recent glibc, which is the one used in most Linux systems: http://www.cs.umaine

问题 Ive look everywhere and whatever algorithm I find (if any lol) for insertion sort on a vector in c++, it wont work so im assuming it has something to do with my code. Can anyone help me find a way I can pass a vector into a method as an argument and then do an insertion sort on it? At the moment it waits for a few seconds and shows all the values unsorted :( Insertion Sort Code void insertionSort (vector<int> data, int n) { int i, j, tmp; for (i=1; i<n; i++) { j=i; tmp=data[i]; while (j>0 &&

问题 I am playing around with x86 assembly for the first time and I can't figure out how to sort an array (via insertion sort).. I understand the algorithm, but assembly is confusing me as I primarily use Java & C++. Heres all I have so far int ascending_sort( char arrayOfLetters[], int arraySize ) { char temp; __asm{ push eax push ebx push ecx push edx push esi push edi //// ??? pop edi pop esi pop edx pop ecx pop ebx pop eax } } Basically nothing :( Any ideas?? Thanks in advance. Ok, this is

问题 I recently read an article that talked about the computation complexity of algorithms. The author mentioned "why insertion sort is faster than quick-sort and bubble-sort for small cases". Could anybody make some explanation for that? Does anybody know the actual complexity of each sort algorithm I mentioned above? 回答1: Consider two complexity functions: F(X) = X^2 G(X) = 4 * X * ln(X) F(3) = 9 G(3) = 13 So algorithm F wins for 3 items. But: F(100) = 10,000 G(100) = 1,842 So algorithm G wins

问题 So I have a MergeSort algorithm and I want to combine MergeSort with Insertion sort to reduce the overhead of merging, the question is how? I want to sort the segments using insertion sort and then merge. public class mergesorttest{ public static void main(String[]args){ int d[]= {10,2,3,4,5,6,5,4,3,5,6,7,1}; mergeSort(d,0,d.length); for(int x:d) System.out.print(x+" "); System.out.println(); } static void mergeSort(int f[],int lb, int ub){ //termination reached when a segment of size 1

问题 I am doing my revision for the exam. Would like to know under what condition will Insertion sort performs better than bubble sort given same average case complexity of O(N^2). I did found some related articles, but I can't understand them. Would anyone mind explaining it in a simple way? 回答1: The advantage of bubblesort is in the speed of detecting an already sorted list: BubbleSort Best Case Scenario: O(n) However, even in this case insertion sort got better/same performance. Bubblesort is,

问题 I've implemented a Linked List class and I have a selectionSort and insertionSort function created that works on regular lists. I need to get selectionSort and insertionSort to work on linked lists, but I'm not sure where to even start, if I'm being honest. Here's my linked list class: class Node: def __init__(self, initdata): self.data = initdata self.next = None def getData(self): return self.data def getNext(self): return self.next def setData(self,newdata): self.data = newdata def setNext