Merge sort

PHOTO EMBED

Tue Nov 07 2023 14:39:00 GMT+0000 (Coordinated Universal Time)

Saved by @70da_vic2002 #c++ 

#include <iostream>
#include <string>
#include <vector>
#include <utility>
#include <iterator>
#include <algorithm>
#include <deque>
#include <cmath>
#include <stack>
#include <queue>
#define endl "\n"
#define ll long long
#define all(v) v.begin(),v.end()
void merge(int array[], int const left,
           int const mid, int const right)
{
    auto const subArrayOne = mid - left + 1;
    auto const subArrayTwo = right - mid;

    // Create temp arrays
    auto *leftArray = new int[subArrayOne],
            *rightArray = new int[subArrayTwo];

    // Copy data to temp arrays leftArray[]
    // and rightArray[]
    for (auto i = 0; i < subArrayOne; i++)
        leftArray[i] = array[left + i];
    for (auto j = 0; j < subArrayTwo; j++)
        rightArray[j] = array[mid + 1 + j];

    // Initial index of first sub-array
    // Initial index of second sub-array
    auto indexOfSubArrayOne = 0,
            indexOfSubArrayTwo = 0;

    // Initial index of merged array
    int indexOfMergedArray = left;

    // Merge the temp arrays back into
    // array[left..right]
    while (indexOfSubArrayOne < subArrayOne &&
           indexOfSubArrayTwo < subArrayTwo)
    {
        if (leftArray[indexOfSubArrayOne] <=
            rightArray[indexOfSubArrayTwo])
        {
            array[indexOfMergedArray] =
                    leftArray[indexOfSubArrayOne];
            indexOfSubArrayOne++;
        }
        else
        {
            array[indexOfMergedArray] =
                    rightArray[indexOfSubArrayTwo];
            indexOfSubArrayTwo++;
        }
        indexOfMergedArray++;
    }

    // Copy the remaining elements of
    // left[], if there are any
    while (indexOfSubArrayOne < subArrayOne)
    {
        array[indexOfMergedArray] =
                leftArray[indexOfSubArrayOne];
        indexOfSubArrayOne++;
        indexOfMergedArray++;
    }

    // Copy the remaining elements of
    // right[], if there are any
    while (indexOfSubArrayTwo < subArrayTwo)
    {
        array[indexOfMergedArray] =
                rightArray[indexOfSubArrayTwo];
        indexOfSubArrayTwo++;
        indexOfMergedArray++;
    }
}

// begin is for left index and end is
// right index of the sub-array
// of arr to be sorted */
void mergeSort(int array[],
               int const begin,
               int const end)
{
    // Returns recursively
    if (begin >= end)
        return;

    auto mid = begin + (end - begin) / 2;
    mergeSort(array, begin, mid);
    mergeSort(array, mid + 1, end);
    merge(array, begin, mid, end);
}




using namespace std;
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

        ll N ;
        cin>>N ;
        int X[N] ;
        for(ll i=0;i<N;i++){
        cin>>X[i];}
    mergeSort(X,0,N-1) ;
    for(ll i=0;i<N;i++){
        cout<<X[i]<<" ";}

}
content_copyCOPY

https://www.onlinegdb.com/online_c++_compiler