//non-recursive非递归 postorder traversal后序遍历
//用栈模拟实现中序遍历
//Push操作的数据过程是先序遍历，Pop操作的数据过程是中序遍历
#include<iostream>
#include<algorithm>
#include<cstring>
#include<vector>
#include<sstream>
#include<stack>

using namespace std;

const int N = 40;

int n;
vector<int> preorder,inorder,postorder;
stack<int> st;

void build(int inL, int inR, int preL,int preR)//建树
{
    if(inL>inR) return;
    int root=preorder[preL];
    int k;
    for(k=inL;k<=inR;k++)
    {
        if(inorder[k]==root)
        {
            build(inL,k-1,preL+1,preL+k-inL);
            build(k+1,inR,preL+k-inL+1,preR);
            postorder.push_back(root);
        }
    }
}
int main()
{
    cin>>n;
    string str;
    getline(cin,str);
    for(int i = 0; i<n*2; i++)
    {
        getline(cin,str);
        stringstream ss(str);
        string a,b;
        ss>>a>>b;
        if(a == "Push")//Push顺序就是前序遍历
        {
            preorder.push_back(stoi(b));
            st.push(stoi(b));
        }
        else//pop出来模拟的是中序遍历
        {
            inorder.push_back(st.top());
            st.pop();
        }
    }
    build(0,n-1,0,n-1);
    for(int i=0;i<n;i++)
    {
        if(i==0) printf("%d",postorder[i]);
        else printf(" %d",postorder[i]);
    }
    return 0;
}