Сортировка

#include <iostream>
#include <Windows.h>
#include <ctime>
using namespace std;

//Быстрая сортировка
int partition(int list[], int start, int pivot)

{
    int i = start;
    while (i < pivot)
    {
        if (list[i] > list[pivot] && i == pivot - 1)
        {
            swap(list[i], list[pivot]);
            pivot--;
        }

        else if (list[i] > list[pivot])
        {
            swap(list[pivot - 1], list[pivot]);
            swap(list[i], list[pivot]);
            pivot--;
        }

        else i++;
    }
    return pivot;
}

void quickSort(int list[], int start, int end)
{
    if (start < end)
    {
        int pivot = partition(list, start, end);

        quickSort(list, start, pivot - 1);
        quickSort(list, pivot + 1, end);
    }
}

int main1()
{
    int list[6] = { 2, 12, 5, 48, 0, 4 };
    cout << "Input array ...\n";
    for (int i = 0; i < 6; i++)
    {
        cout << list[i] << "\t";
    }

    quickSort(list, 0, 6);

    cout << "\n\nSorted array ... \n";
    for (int i = 0; i < 6; i++)
    {
        cout << list[i] << "\t";
    }

    return 0;
}
//СОРТИРОВКА СЛИЯНИЕМ
void merge(int list[], int start, int end, int mid);

void mergeSort(int list[], int start, int end)
{
    int mid;
    if (start < end) {

        mid = (start + end) / 2;
        mergeSort(list, start, mid);
        mergeSort(list, mid + 1, end);
        merge(list, start, end, mid);
    }
}

void merge(int list[], int start, int end, int mid)
{
    int mergedList[8];
    int i, j, k;
    i = start;
    k = start;
    j = mid + 1;

    while (i <= mid && j <= end) {
        if (list[i] < list[j]) {
            mergedList[k] = list[i];
            k++;
            i++;
        }
        else {
            mergedList[k] = list[j];
            k++;
            j++;
        }
    }

    while (i <= mid) {
        mergedList[k] = list[i];
        k++;
        i++;
    }

    while (j <= end) {
        mergedList[k] = list[j];
        k++;
        j++;
    }

    for (i = start; i < k; i++) {
        list[i] = mergedList[i];
    }
}

int main2()
{
    int list[8] = { 3,19,8,0,48,4,5,12 };
    cout << "Input array ...\n";
    for (int i = 0; i < 8; i++)
    {
        cout << list[i] << "\t";
    }
    mergeSort(list, 0, 7);
    cout << "\n\nSorted array ... \n";
    for (int i = 0; i < 8; i++)
    {
        cout << list[i] << "\t";
    }
    return 0;
}
//ПУЗЫРЬКОВАЯ СОРТИРОВКА
void bubbleSort(int list[], int listLength)
{
    while (listLength--)
    {
        bool swapped = false;

        for (int i = 0; i < listLength; i++)
        {
            if (list[i] > list[i + 1])
            {
                swap(list[i], list[i + 1]);
                swapped = true;
            }
        }

        if (swapped == false)
            break;
    }
}

int main3()
{
    int list[5] = { 3,19,8,0,48 };
    cout << "Input array ..." << endl;
    for (int i = 0; i < 5; i++)
        cout << list[i] << '\t';
    cout << endl;

    bubbleSort(list, 5);

    cout << "Sorted array ..." << endl;
    for (int i = 0; i < 5; i++)
        cout << list[i] << '\t';
    cout << endl;

    return 0;
}
//Сортировка выбором
int findSmallestPosition(int list[], int startPosition, int listLength)
{
    int smallestPosition = startPosition;

    for (int i = startPosition; i < listLength; i++)
    {
        if (list[i] < list[smallestPosition])
            smallestPosition = i;
    }
    return smallestPosition;
}

void selectionSort(int list[], int listLength)
{
    for (int i = 0; i < listLength; i++)
    {
        int smallestPosition = findSmallestPosition(list, i, listLength);
        swap(list[i], list[smallestPosition]);
    }
    return;
}

int main4()
{
    int list[5] = { 12, 5, 48, 0, 4 };

    cout << "Input array ..." << endl;
    for (int i = 0; i < 5; i++)
        cout << list[i] << '\t';
    cout << endl;

    selectionSort(list, 5);

    cout << "Sorted array ..." << endl;
    for (int i = 0; i < 5; i++)
        cout << list[i] << '\t';
    cout << endl;
    return 0;
}

int main()
{
    srand(time(0));
    cout << "Choose sorting 1 - 4" << endl;
    int n;
    cin >> n;
    switch (n)
            {
    case 1:
        cout << "Quick sorting" << endl;
        main1();
        cout << "\n  runtime = " << clock() / 1000.0 << endl;
        break;

    case 2:
        cout << "MERGE SORTING" << endl;
        main2();
        cout << " \n  runtime = " << clock() / 1000.0 << endl;
        break;
    case 3:
        cout << " \n BUBBLE SORTING" << endl;
        main3();
        cout << " \n  runtime =  " << clock() / 1000.0 << endl;
        break;
    case 4:
        cout << "Sorting by choice" << endl;
        cout << " \n runtime =" << clock() / 1000.0 << endl;
        main4();
        break;
        }
    system("pause");
    return 0;
}