#include <stdio.h>
#include <stdbool.h>
void merge(int arr[],int left,int mid,int right){
    int i,j,k;
    int n1=mid-left+1;
    int n2=right-mid;
    int L[n1],R[n2];
    for(i=0;i<n1;i++)
      L[i] = arr[left+i];
    for(j=0;j<n2;j++)
      R[j]=arr[mid+1+j];
      i=0;
      j=0;
      k=left;
      while(i<n1&&j<n2){
          if(L[i]<=R[j]){
              arr[k]=L[i];
              i++;
          }else{
              arr[k]=R[j];
              j++;
          }
          k++;
      }
      while(i<n1){
          arr[k]=L[i];
          i++;
          k++;
      }
      while(j<n2){
          arr[k]=R[j];
          j++;
          k++;
      }
}