Answers for "what does merge sort do"

merge sort

void merge(int arr[], int l, int m, int r)
    {
         int n=r-l+1,temp[n];
         int i=l,j=m+1,k=0;
         while(i<=m and j<= r)
         {
             if(arr[i]< arr[j]){
                temp[k++] = arr[i++];
             else
                temp[k++] = arr[j++];
         }
         while(i<=m)
            temp[k++] = arr[i++];
         while(j<=r)
            temp[k++] = arr[j++];
         int ind= 0;
         for(int i=l;i<=m;i++)
             arr[i] = temp[ind++];
         for(int j=m+1;j<=r;j++)
            arr[j] = temp[ind++];
    }
    
    void mergeSort(int arr[], int l, int r)
    {
       if(l<r)
       {
           int mid = (r+l)/2;
           mergeSort(arr,l,mid);
           mergeSort(arr,mid+1,r);
           merge(arr,l,mid,r);
       }
    }