#include <bits/stdc++.h>
#define all(x) x.begin() , x.end()
#define CLR( x ) memset(x , 0 , sizeof x)
#define pb push_back
#define mp make_pair
#define f first
#define s second
#define ii pair<int , int>
#define vi vector< int >
#define vl vector < long long >
#define vs vector < string >
#define vb vector < bool >
#define max3(a , b , c) max(a , max(b , c))
#define min3(a , b , c) min(a , min(b , c))
#define oo 10000000
#define mod 1000000007
typedef long long ll ;
typedef unsigned long long ull ;
using namespace std ;
stack<int> sorting ;
priority_queue<int> pq;
void re()
{
    if(sorting.empty())
        return ;
    int inPut = sorting.top() ;
    sorting.pop() ;
    re() ;
    pq.push(inPut) ;
}
void addToStack()
{
    if(pq.empty())
        return ;
    int inPut = pq.top() ;
    pq.pop() ;
    addToStack() ;
    sorting.push(inPut) ;
}
int main()
{
    ios_base::sync_with_stdio(0);
    sorting.push(5) ;
    sorting.push(6) ;
    sorting.push(4) ;
    re() ;
    addToStack() ;
    while(!sorting.empty())
    {
        cout << sorting.top() << " " ;
        sorting.pop() ;
    }
    return 0;
}