#include <algorithm>
#include <cstdio>
#include <iostream>
using namespace std;

typedef struct Node{
    char data;
    Node * lc;
    Node * rc;
}Node;

const int N = 105;
string pre;
int pos;
Node* create(){
    if(pos >= pre.length()){
        return NULL;
    }
    if(pre.at(pos) == '#')
        return NULL;
    Node* p = new Node();
    p->data = pre.at(pos);
    pos++;
    p->lc = create();
    cout << p->data << " ";
    pos++;
    p->rc = create();
    return p;
}

int main(){
    cin >> pre;
    create();
    system("pause");
    return 0;
}