MergeSort.c

#include<stdio.h>
void merge(int arr[],int left,int mid,int right)
{
  int n1 = mid - left + 1;
  int n2 = right - mid;
  int L[n1], R[n2];
  for (int i = 0; i < n1;i++)
    L[i] = arr[left + i];
  for (int j = 0; j < n2;j++)
    R[j] = arr[right + 1 + j];
  int j = 0, i = 0, k = left;
  while(i<n1 && j<n2)
  {
    if(L[i]>R[j])
    {
      arr[k] = L[i];
      k++;
      i++;
    }
    else
    {
      arr[k] = R[j];
      k++;
      j++;
    }
  }
  while(i<n1)
  {
    arr[k] = L[i];
    k++;
    i++;
  }
  while(i<n2)
  {
    arr[k] = R[j];
    k++;
    j++;
  }
}
void mergeSort(int arr[],int left,int right)
{
  if (left<right)
  {
    int mid = left + (right - left) / 2;
    mergeSort(arr, left, mid);
    mergeSort(arr, mid + 1, right);
    merge(arr, left, mid, right);
  }
}
void main()
{
  int n, arr[50];
  printf("Enter the length of the array ");
  scanf("%d", &n);
  printf("Enter the elements of the array ");
  for (int i = 0; i < n; i++)
  {
    scanf("%d", &arr[i]);
  }
  mergeSort(arr, 0,n-1);
  printf("the sorted array is: ");
  for (int i = 0; i < n; i++)
  {
    printf("%d ", arr[i]);
  }
}