Shell-Metzner Sort
Given an array arr[] of N integers, the task is to sort the array using Shell-Metzner sort.
Input: arr[] = {0, -2, 8, 5, 1}
Output: -2 0 1 5 8
Input: arr[] = {4, 5, 6, 1, 100000, 1000}
Output: 1 4 5 6 1000 100000
Prerequisite: Shell Sort
The Shell-Metzner sort is an adaptation of the Shell sort by Marlene Metzner. The Shell-Metzner Sort uses five indices to check which cells to swap. The Metzner version starts with a step size equal to half the length of the array, with each pass increasing the number of comparisons quadratically.
Below is the implementation of Shell-Metzner sort:
C++
// C++ implementation of Shell-Metzner Sort#include <bits/stdc++.h>using namespace std;// Function to swap two elementsvoid swap(int& a, int& b){ int temp = a; a = b; b = temp;}// Function to sort arr[] using Shell Metzner sortvoid sort_shell_metzner(int arr[], int n){ // Declare variables int i, j, k, l, m, temp; // Set initial step size to // the size of the array m = n; while (m > 0) { // Step size decreases by half each time m /= 2; // k is the upper limit for j k = n - m; // j is the starting point j = 0; do { // i equals to smaller value i = j; do { // l equals to larger value l = i + m; // Compare and swap arr[i] with arr[l] if (arr[i] > arr[l]) { swap(arr[i], arr[l]); // Decrease smaller value by step size i -= m; } else break; } while (i >= 0); // Increment the lower limit of i j++; } while (j <= k); }}// Function to print the contents of an arrayvoid printArray(int arr[], int n){ for (int i = 0; i < n; i++) cout << arr[i] << " ";}// Driver codeint main(){ int arr[] = { 0, -2, 8, 5, 1 }; int n = sizeof(arr) / sizeof(arr[0]); // Sort the array using Shell Metzner Sort sort_shell_metzner(arr, n); // Print the sorted array printArray(arr, n); return 0;} |
Java
// Java implementation of Shell-Metzner Sortclass GFG{ // Function to swap two elements static int[] swap(int[] arr, int i, int j) { int temp = arr[i]; arr[i] = arr[j]; arr[j] = temp; return arr; } // Function to sort arr[] using Shell Metzner sort static void sort_shell_metzner(int arr[], int n) { // Declare variables int i, j, k, l, m, temp; // Set initial step size to // the size of the array m = n; while (m > 0) { // Step size decreases by half each time m /= 2; // k is the upper limit for j k = n - m; // j is the starting point j = 0; do { // i equals to smaller value i = j; do { // l equals to larger value l = i + m; // Compare and swap arr[i] with arr[l] if (l < n && arr[i] > arr[l]) { swap(arr, i, l); // Decrease smaller value by step size i -= m; } else { break; } } while (i >= 0); // Increment the lower limit of i j++; } while (j <= k); } } // Function to print the contents of an array static void printArray(int arr[], int n) { for (int i = 0; i < n; i++) { System.out.print(arr[i] + " "); } } // Driver code public static void main(String[] args) { int arr[] = {0, -2, 8, 5, 1}; int n = arr.length; // Sort the array using Shell Metzner Sort sort_shell_metzner(arr, n); // Print the sorted array printArray(arr, n); }}/* This code contributed by PrinciRaj1992 */ |
Python3
# Python3 implementation of Shell-Metzner Sort# Function to sort arr[] using Shell Metzner sortdef sort_shell_metzner( arr, n): # Set initial step size to # the size of the array m = n; while (m > 0): # Step size decreases by half each time m //= 2 # k is the upper limit for j k = n - m # j is the starting point j = 0 while(j < k): # i equals to smaller value i = j while(i >= 0): # l equals to larger value l = i + m # Compare and swap arr[i] with arr[l] if (arr[i] > arr[l]): arr[i], arr[l]=arr[l],arr[i] # Decrease smaller value by step size i -= m else: break # Increment the lower limit of i j += 1# Function to print the contents of an arraydef printArray(arr, n): for i in range( n): print( arr[i], end= " ")# Driver codeif __name__ =="__main__": arr = [ 0, -2, 8, 5, 1 ] n = len(arr) # Sort the array using Shell Metzner Sort sort_shell_metzner(arr, n) # Print the sorted array printArray(arr, n)# This code is contributed by chitranayal |
C#
// C# implementation of Shell-Metzner Sortusing System;class GFG{ // Function to swap two elements static int[] swap(int[] arr, int i, int j) { int temp = arr[i]; arr[i] = arr[j]; arr[j] = temp; return arr; } // Function to sort arr[] using Shell Metzner sort static void sort_shell_metzner(int []arr, int n) { // Declare variables int i, j, k, l, m, temp; // Set initial step size to // the size of the array m = n; while (m > 0) { // Step size decreases by half each time m /= 2; // k is the upper limit for j k = n - m; // j is the starting point j = 0; do { // i equals to smaller value i = j; do { // l equals to larger value l = i + m; // Compare and swap arr[i] with arr[l] if (l < n && arr[i] > arr[l]) { swap(arr, i, l); // Decrease smaller value by step size i -= m; } else { break; } } while (i >= 0); // Increment the lower limit of i j++; } while (j <= k); } } // Function to print the contents of an array static void printArray(int []arr, int n) { for (int i = 0; i < n; i++) { Console.Write(arr[i] + " "); } } // Driver code public static void Main(String[] args) { int []arr = {0, -2, 8, 5, 1}; int n = arr.Length; // Sort the array using Shell Metzner Sort sort_shell_metzner(arr, n); // Print the sorted array printArray(arr, n); }}// This code has been contributed by 29AjayKumar |
PHP
<?php// php implementation of Shell-Metzner Sort// Function to sort arr[] using Shell Metzner sortfunction sort_shell_metzner($arr, $n){ // Set initial step size to // the size of the array $m = $n; while ($m > 0) { // Step size decreases by half each time $m = $m / 2; // k is the upper limit for j $k = $n - $m; // j is the starting point $j = 0; do { // i equals to smaller value $i = $j; do { // l equals to larger value $l = $i + $m; // Compare and swap arr[i] with arr[l] if ($arr[$i] > $arr[$l]) { $temp = $arr[$i]; $arr[$i] = $arr[$l]; $arr[$l] = $temp; // Decrease smaller value by step size $i -= $m; } else break; } while ($i >= 0); // Increment the lower limit of i $j++; } while ($j <= $k); } return $arr ;}// Function to print the contents of an arrayfunction printArray($arr, $n){ for ($i = 0; $i < $n; $i++) echo $arr[$i], " ";}// Driver code$arr = array( 0, -2, 8, 5, 1 );$n = count($arr);// Sort the array using Shell Metzner Sort$result_array = sort_shell_metzner($arr, $n);// Print the sorted arrayprintArray($result_array, $n);// This code is contributed by Ryuga?> |
Javascript
<script>// JavaScript implementation of Shell-Metzner Sort// Function to swap two elements function swap(arr,i,j) { let temp = arr[i]; arr[i] = arr[j]; arr[j] = temp; return arr; } // Function to sort arr[] using Shell Metzner sort function sort_shell_metzner(arr,n) { // Declare variables let i, j, k, l, m, temp; // Set initial step size to // the size of the array m = n; while (m > 0) { // Step size decreases by half each time m = Math.floor(m/2); // k is the upper limit for j k = n - m; // j is the starting point j = 0; do { // i equals to smaller value i = j; do { // l equals to larger value l = i + m; // Compare and swap arr[i] with arr[l] if (l < n && arr[i] > arr[l]) { swap(arr, i, l); // Decrease smaller value by step size i -= m; } else { break; } } while (i >= 0); // Increment the lower limit of i j++; } while (j <= k); } } // Function to print the contents of an array function printArray(arr,n) { for (let i = 0; i < n; i++) { document.write(arr[i] + " "); } } // Driver code let arr=[0, -2, 8, 5, 1]; let n = arr.length; // Sort the array using Shell Metzner Sort sort_shell_metzner(arr, n); // Print the sorted array printArray(arr, n);// This code is contributed by avanitrachhadiya2155</script> |
Output:
-2 0 1 5 8
Time Complexity: O(n2)
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