#define HAVE_STRUCT_TIMESPEC

 #include<bits/stdc++.h>

 using namespace std;

 int a[][];

 bool vis[];

 void bfs(int r){

     queue<int>q;

     q.push(r);

     cout<<r;

     while(!q.empty()){

         int now=q.front();

         q.pop();

         if(a[now][]!=-){

             cout<<" ";

             cout<<a[now][];

             q.push(a[now][]);

         }

         if(a[now][]!=-){

             cout<<" ";

             cout<<a[now][];

             q.push(a[now][]);

         }

     }

 }

 int flag=;

 void dfs(int r){

     if(a[r][]!=-)

         dfs(a[r][]);

     if(flag)

         cout<<" ";

     cout<<r;

     flag=;

     if(a[r][]!=-)

         dfs(a[r][]);

 }

 int main(){

     ios::sync_with_stdio(false);

     cin.tie(NULL);

     cout.tie(NULL);

     for(int i=;i<;++i)

         a[i][]=a[i][]=-;

     int n;

     cin>>n;

     for(int i=;i<n;++i){

         char x;

         cin.ignore();

         cin>>x;

         cin.ignore();

         if(x!='-')

             a[i][]=x-'',vis[x-'']=;

         char y;

         cin>>y;

         if(y!='-')

             a[i][]=y-'',vis[y-'']=;

     }

     int root=;

     for(int i=;i<n;++i)

         if(!vis[i])

             root=i;

     bfs(root);

     cout<<"\n";

     dfs(root);

     return ;

 }