merge.txt

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
#define IOS ios_base::sync_with_stdio(0);  cin.tie(0); cout.tie(0);
#define yes cout<<"YES"<<endl
#define no cout<<"NO"<<endl
#define vi vector<int>
#define vll vector<long long>
#define mp make_pair
#define MPII map<int,int>
#define MPLL map<long long,long long>
#define MPSI map<string,int>
#define MPIS map<int,string>
#define PRII pair<int,int>
#define PRLL pair<long long,long long>
#define SP cout<<fixed<<setprecision(10);
#define rep(i,inval,n) for(int i = inval; i < n; i++)
#define all(x) x.begin(),x.end()
const int inf = 1e9 + 10;
const ll INF = 1e18 + 10;

void Merge(int arr[],int left,int right,int mid)
{
    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[i+left];
    }

    for( i=0;i<n2;i++)
    {
        R[i]=arr[i+mid+1];
    }

    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++;
    }


}

void merge_sort(int arr[],int left,int right)
{
   if(left<right)
   {
      int mid=left+(right-left)/2;

    merge_sort(arr,left,mid);
    merge_sort(arr,mid+1,right);


    Merge(arr,left,right,mid);
   }

}

int main()
{
    IOS;

    int t=1;
   // cin>>t;
    while(t--)
    {
        int n;
        cin>>n;
        int arr[n];
        for(int i=0;i<n;i++) cin>>arr[i];
         merge_sort(arr,0,n-1);
        for(int i=0;i<n;i++) cout<<arr[i]<<" ";
           cout<<endl;

    }

    return 0;
}