logo
down
shadow

How to sort in-place using the merge sort algorithm?


How to sort in-place using the merge sort algorithm?

By : Sayoni
Date : November 20 2020, 07:00 PM
Does that help Knuth left this as an exercise (Vol 3, 5.2.5). There do exist in-place merge sorts. They must be implemented carefully.
First, naive in-place merge such as described here isn't the right solution. It downgrades the performance to O(N2).
code :


Share : facebook icon twitter icon
What is the fastest simple sorting algorithm (except quick sort/merge sort) for 500 numbers?

What is the fastest simple sorting algorithm (except quick sort/merge sort) for 500 numbers?


By : Azharuddin
Date : March 29 2020, 07:55 AM
To fix the issue you can do I once compared some sorting algorithms. I found comb sort and heap sort are very easy to implement and give very good results.
code :
void comb_sort(double *a, int size) {
    int gap = size;
    bool swapped = false;
     while ((gap > 1) || swapped) {
        if (gap > 1) gap = int(gap/1.247330950103979);
        swapped = false;
        for (int i = 0; gap + i < size; i++)
        if (a[i + gap] < a[i]) {
           swap(&a[i + gap], &a[i]);
           swapped = true;
        }
    }
}
How to sort a big array consists of four sorted parts, preferably by merge sort algorithm?

How to sort a big array consists of four sorted parts, preferably by merge sort algorithm?


By : LemonMan
Date : March 29 2020, 07:55 AM
Any of those help You don't need to do a merge sort. You just need to do the merge operations in-place 3 times (1st part merge 2nd part; 3rd part merge 4th part; then merge those two). Note that merge is an O(n) operation, which is what makes a merge sort work. So this algorithm will be O(n) + O(n) + O(n) = O(n).
O(n) is optimal since you will need to access each element at least once no matter what. (So the problem, and this algorithm, are Omega(n) and Theta(n) as well, for what it's worth.)
Why does my merge sort algorithm not sort my array correctly?

Why does my merge sort algorithm not sort my array correctly?


By : user3257278
Date : March 29 2020, 07:55 AM
around this issue I think the problem is in array reference in C# as @canton7 said, try this code:
code :
private static int[] data = new int[] { 1, 9, 10, 2, 4, 5, 6 };
private static int[] intArray;

static void Main()
{
    int N = data.Length;
    intArray = new int[N];
    Sort(0, N - 1);
    for (int i = 0; i < N; i++)
        Console.WriteLine(intArray[i]);
}

private static void Merge(int lo, int mid, int hi)
{
    int i = lo;
    int j = mid + 1;      
    for (int k = lo; k <= hi; k++)
    {
        if (i > mid)
            intArray[k] = data[j++];
        else if (j > hi)
            intArray[k] = data[i++];
        else if (data[j] < data[i])
            intArray[k] = data[j++];
        else if (data[i] < data[j])
            intArray[k] = data[i++];
    }
    if (intArray.Length != 0)
        for (int k = lo; k <= hi; k++)
            data[k] = intArray[k];
}

private static void Sort(int lo, int hi)
{
    if (hi == lo)
        return;
    int mid = lo + (hi - lo) / 2;
    Sort(lo, mid);
    Sort(mid + 1, hi);
    Merge(lo, mid, hi);
}
Counting comparisons in selection sort, insertion sort, merge sort, and quick sort?

Counting comparisons in selection sort, insertion sort, merge sort, and quick sort?


By : J.Young Tsang
Date : March 29 2020, 07:55 AM
This might help you Since your question is not marked as homework, I assume you mainly want to find out how many comparisons are made during sorting. For this, I would
not reinvent sorting but use highly efficient sorting from the Java library use an own Comparator that decorates an existing compare() or compareTo() to count the number of comparisons.
How is shell sort algorithm any better than of merge sort algorithm?

How is shell sort algorithm any better than of merge sort algorithm?


By : supto
Date : March 29 2020, 07:55 AM
fixed the issue. Will look into that further You have to remember the context in which shellsort was proposed: shellsort was published in 1959; quicksort, in 1961; mergesort, in 1948 (OK, that was a bit surprising). The computers of the day were slow and had small memories. Thus the asymptotic advantage of mergesort was hardly relevant compared to the increased complexity of implemention and code. In fact, shellsort gets the quadratic fallback of modern practical mergesorts for free, since insertion sorting with a gap of 1 is insertion sort.
It was not known then how to do an efficient in-place merge (and even now, no one implements it, because it's wildly inefficient in practice).
Related Posts Related Posts :
  • transpose 1D array of leading dimension N
  • passing an array of structures (containing two mpz_t numbers) to a function
  • Finding whether a value is equal to the value of any array element in MATLAB
  • How to do this in a better way
  • "array out of range" when I tried to build in an indicator (SMA of the RSI line) to my EA
  • Creating and inputting data into nested arrays - Ruby
  • Divide array into sub arrays such that no sub array contains duplicate elements
  • How to pick multiple array elements in swift 4.2?
  • Getting an specified object from array and take this as a variable
  • Apply function to pairs of columns in Julia
  • How can I remove rows of a matrix in Matlab when the difference between two consecutive rows is more than a threshold?
  • How to insert objects in array next to objects with the same property value
  • Unable to convert varchar to array in Presto Athena
  • Using VBA in Excel, how do you Hide columns that do not have a header specified in an array?
  • `replace` versus plain `loop` for copying large arrays in SBCL
  • Multiplication of corresponding values in an array
  • VBA Error: How do I define and initialize an Array in VBA
  • VBA ARRAY definition does not work for global definitions
  • json array character value ascending and descending order typescript
  • multi-select dropdown and form field shows as array?
  • Mapping function to list/array in haskell?
  • The longest length of most consecutive number which is bigger than zero in a series
  • Array with `n` elements in Kotlin doesn't work
  • Parse a JSON object with the value as JSON string array
  • Flutter - Create list and 'addAll' in same instruction
  • Having multiple separate arrays of data, is there any other more efficient method to merge them into objects?
  • Processing large arrays in PowerShell
  • Selecting Distinct Items within Array using PowerShell and Linq
  • Selecting elements from a vector based on condition on another vector
  • Converting multiple variables in SAS from 0/1 to 'Yes'/'No'
  • Excel VBA Arrays: Is there a simple way to delete a dataset by the index?
  • Ruby - how to slice an array and sum its elements on a condition
  • How to avoid adding to an array if element already exists
  • why val not affect to the array in KOTLIN?
  • Is there an easy way to compute difference between two arrays
  • Insert a smallest possible positive integer into an array of unique integers
  • Revising a Ruby method to represent integer partition as ordered string (without flattening?)
  • What goes wrong in my array comparison code?
  • How to zip a 2D and a 1D array row-wise in Julia?
  • Subscript out of range, moving data from range to array
  • How to search inside array in reactjs
  • Why does min value return as zero and max return as a proper value
  • How can I find if the index number for a specific item in an array also exists as an integer in the same array?
  • cmp instruction not making jge jump within InsertionSort
  • Preallocating memory for variable that changes size every iteration (long text file)
  • Converting a cell to a 4D array
  • How to redistribute content of a 2-d array?
  • perl call variable name using another variable(array)
  • V-lang shows V panic: array index out of range error for valid indexing of array after V panic is encountered once
  • Is array declaration in Kotlin with size possible just with initialization?
  • Kotlin array <init>ialization
  • bash string to array and array to string
  • Removing items from array in custom tableViewCell
  • Initialize Array of non-optionals without using constructor
  • For Loop Issues in creating nested array
  • Adverse Events table in SAS
  • Problem to get more than 1 element with same highest occurrence from array in Perl
  • How Would I Format An Array Like This?
  • Why does my Ruby method return an array instead of the string?
  • How to create a custom hashtable with arrays of objects - powershell / cmd
  • shadow
    Privacy Policy - Terms - Contact Us © 35dp-dentalpractice.co.uk