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fix issues from #929
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@ -4,22 +4,18 @@
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* \brief [Insertion Sort Algorithm
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* (Insertion Sort)](https://en.wikipedia.org/wiki/Insertion_sort)
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*
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* \author
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*
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* \details
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* Insertion sort is a simple sorting algorithm that builds the final
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* sorted array one at a time. It is much less efficient compared to
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* other sorting algorithms like heap sort, merge sort or quick sort.
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* However it has several advantages such as
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* <pre>
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* 1 - easy to implement
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* 2 - For small set of data it is quite efficient
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* 3 - More efficient that other Quadratic complexity algorithms like
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* Selection sort or bubble sort.
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* 4 - It's stable that is it does not change the relative order of
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* elements with equal keys
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* 5 - Works on hand means it can sort the array or list as it receives.
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* </pre>
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* 1. easy to implement
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* 2. For small set of data it is quite efficient
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* 3. More efficient that other Quadratic complexity algorithms like
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* Selection sort or bubble sort.
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* 4. It's stable that is it does not change the relative order of
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* elements with equal keys
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* 5. Works on hand means it can sort the array or list as it receives.
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*
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* It is based on the same idea that people use to sort the playing cards in
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* their hands.
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@ -27,44 +23,41 @@
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* of elements as soon as we find a unsorted element that is a misplaced
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* element we place it at a sorted position.
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*
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* Suppose initially we have
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* <pre>
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* 4 3 2 5 1
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*
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* we start traversing from 4 till we reach 1
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* Execution example steps:
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* 1. Suppose initially we have
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* <pre>4 3 2 5 1</pre>
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* 2. We start traversing from 4 till we reach 1
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* when we reach at 3 we find that it is misplaced so we take 3 and place
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* it at a correct position thus the array will become
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*
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* 3 4 2 5 1
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*
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* in the next iteration we are at 2 we find that this is also misplaced so
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* <pre>3 4 2 5 1</pre>
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* 3. In the next iteration we are at 2 we find that this is also misplaced so
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* we place it at the correct sorted position thus the array in this iteration
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* becomes
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*
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* 2 3 4 5 1
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*
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* we does not do anything with 5 and move on to the next iteration and select
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* 1 which is misplaced and place it at correct position. Thus, we have
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*
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* 1 2 3 4 5
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* </pre>
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*
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* <pre>2 3 4 5 1</pre>
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* 4. we does not do anything with 5 and move on to the next iteration and
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* select 1 which is misplaced and place it at correct position. Thus, we have
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* <pre>1 2 3 4 5</pre>
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*/
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#include <algorithm>
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#include <cassert>
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#include <iostream>
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#include <vector>
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/** \namespace sorting
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* \brief Sorting algorithms
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*/
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namespace sorting {
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/** \brief
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* Insertion Sort Function
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*
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* @param arr Array to be sorted
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* @param n Size of Array
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*
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*/
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void insertionSort(int *arr, int n) {
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template <typename T>
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void insertionSort(T *arr, int n) {
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for (int i = 1; i < n; i++) {
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int temp = arr[i];
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T temp = arr[i];
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int j = i - 1;
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while (j >= 0 && temp < arr[j]) {
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arr[j + 1] = arr[j];
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@ -74,17 +67,48 @@ void insertionSort(int *arr, int n) {
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}
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}
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template <typename T>
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void insertionSort(std::vector<T> *arr) {
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size_t n = arr->size();
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for (size_t i = 1; i < n; i++) {
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T temp = arr[0][i];
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int32_t j = i - 1;
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while (j >= 0 && temp < arr[0][j]) {
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arr[0][j + 1] = arr[0][j];
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j--;
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}
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arr[0][j + 1] = temp;
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}
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}
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} // namespace sorting
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/** Test Cases to test algorithm */
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void tests() {
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int arr1[10] = {78, 34, 35, 6, 34, 56, 3, 56, 2, 4};
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insertionSort(arr1, 10);
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std::cout << "Test 1... ";
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sorting::insertionSort(arr1, 10);
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assert(std::is_sorted(arr1, arr1 + 10));
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std::cout << "Test 1 Passed" << std::endl;
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std::cout << "passed" << std::endl;
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int arr2[5] = {5, -3, 7, -2, 1};
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insertionSort(arr2, 5);
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std::cout << "Test 2... ";
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sorting::insertionSort(arr2, 5);
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assert(std::is_sorted(arr2, arr2 + 5));
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std::cout << "Test 2 Passed" << std::endl;
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std::cout << "passed" << std::endl;
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float arr3[5] = {5.6, -3.1, -3.0, -2.1, 1.8};
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std::cout << "Test 3... ";
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sorting::insertionSort(arr3, 5);
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assert(std::is_sorted(arr3, arr3 + 5));
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std::cout << "passed" << std::endl;
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std::vector<float> arr4({5.6, -3.1, -3.0, -2.1, 1.8});
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std::cout << "Test 4... ";
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sorting::insertionSort(&arr4);
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assert(std::is_sorted(std::begin(arr4), std::end(arr4)));
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std::cout << "passed" << std::endl;
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}
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/** Main Function */
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@ -93,9 +117,13 @@ int main() {
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tests();
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/// For user insteraction
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int n;
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std::cout << "Enter the length of your array : ";
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size_t n;
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std::cout << "Enter the length of your array (0 to exit): ";
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std::cin >> n;
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if (n == 0) {
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return 0;
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}
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int *arr = new int[n];
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std::cout << "Enter any " << n << " Numbers for Unsorted Array : ";
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@ -103,7 +131,7 @@ int main() {
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std::cin >> arr[i];
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}
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insertionSort(arr, n);
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sorting::insertionSort(arr, n);
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std::cout << "\nSorted Array : ";
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for (int i = 0; i < n; i++) {
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