Insertion Sort Algorithm (Insertion Sort) More...

#include <algorithm>
#include <cassert>
#include <iostream>

Include dependency graph for insertion_sort.cpp:

Functions
void	insertionSort (int *arr, int n)
	Insertion Sort Function. More...

void	tests ()

int	main ()

Detailed Description

Insertion Sort Algorithm (Insertion Sort)

Author

Insertion sort is a simple sorting algorithm that builds the final sorted array one at a time. It is much less efficient compared to other sorting algorithms like heap sort, merge sort or quick sort. However it has several advantages such as

1 - easy to implement
2 - For small set of data it is quite efficient
3 - More efficient that other Quadratic complexity algorithms like
    Selection sort or bubble sort.
4 - It's stable that is it does not change the relative order of
    elements with equal keys
5 - Works on hand means it can sort the array or list as it receives.

It is based on the same idea that people use to sort the playing cards in their hands. the algorithms goes in the manner that we start iterating over the array of elements as soon as we find a unsorted element that is a misplaced element we place it at a sorted position.

Suppose initially we have

4 3 2 5 1

we start traversing from 4 till we reach 1
when we reach at 3 we find that it is misplaced so we take 3 and place
it at a correct position thus the array will become

3 4 2 5 1

in the next iteration we are at 2 we find that this is also misplaced so
we place it at the correct sorted position thus the array in this iteration
becomes

2 3 4 5 1

we does not do anything with 5 and move on to the next iteration and select
1 which is misplaced and place it at correct position. Thus, we have

1 2 3 4 5

Function Documentation

◆ insertionSort()

void insertionSort	(	int *	arr,
		int	n
	)

Insertion Sort Function.

Parameters

arr	Array to be sorted
n	Size of Array

                                     {
     for (int i = 1; i < n; i++) {
         int temp = arr[i];
         int j = i - 1;
         while (j >= 0 && temp < arr[j]) {
             arr[j + 1] = arr[j];
             j--;
         }
         arr[j + 1] = temp;
     }
 }

◆ main()

int main ( )

Main Function

Running predefined tests to test algorithm

For user insteraction

            {
     /// Running predefined tests to test algorithm
     tests();
  
     /// For user insteraction
     int n;
     std::cout << "Enter the length of your array : ";
     std::cin >> n;
     int *arr = new int[n];
     std::cout << "Enter any " << n << " Numbers for Unsorted Array : ";
  
     for (int i = 0; i < n; i++) {
         std::cin >> arr[i];
     }
  
     insertionSort(arr, n);
  
     std::cout << "\nSorted Array : ";
     for (int i = 0; i < n; i++) {
         std::cout << arr[i] << " ";
     }
  
     std::cout << std::endl;
     delete[] arr;
     return 0;
 }

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◆ tests()

void tests ( )

Test Cases to test algorithm