#define _CRT_SECURE_NO_WARNINGS
#include <vector>
#include <stack>
#include <string>
#include <iostream>
#include <algorithm>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <fstream>
#include <map>
#include <set>
#include <deque>
#include <sstream>
#include <queue>
#include <string.h>
#pragma comment(linker,"/STACK:16777216")

using namespace std;

//Loops
#define FOR(i,a,b) for(int (i) = (a); (i) <= (b); ++(i))
#define ROF(i,a,b) for(int (i) = (a); (i) >= (b); --(i))
#define rep(i,n) for (int (i) = 0; (i) < (n); ++(i))
#define fe(i,a) for (int (i) = 0; (i) < int((a).size()); ++(i))
#define MEM(a,b) memset((a),(b),sizeof(a))

//Constants
#define inf 1000000000
#define pi 2*acos(0.0)
#define N 200010
#define eps 1e-9

//Functions
#define pb push_back
#define ppb pop_back
#define all(c) (c).begin(), (c).end()
#define sz(x) int((x).size())
#define sqr(a) (a)*(a)

//Pairs
#define mp(a,b) make_pair((a), (b))
#define X first
#define Y second

//Input-Output
#define FREOPEN(a,b) freopen(a,"r",stdin); freopen(b,"w",stdout);

typedef vector<int> vint;
typedef long long ll;
typedef pair<int, int> pii;

const long long mod = 1ll << 32;

class Deque{
private :
  struct Node{
      Node *next, *prev;
      int val;
      Node(int _val) : val(_val), prev(NULL), next(NULL) {}
  };
  typedef Node * PNode;
  PNode tail;
public :
  Deque(){
      tail = NULL;
  }
  void push_back(int value){
      PNode cur = new Node(value);
      if (tail == NULL){
          tail = cur;
          tail->next = tail;
          tail->prev = tail;
      }
      else {
          cur->next = tail->next;
          tail->next->prev = cur;
          tail->next = cur;
          cur->prev = tail;
          tail = cur;
      }
  }

  void push_front(int value){
      PNode cur = new Node(value);
      if (tail == NULL){
          tail = cur;
          tail->next = tail;
          tail->prev = tail;
      }
      else {
          cur->next = tail->next;
          tail->next->prev = cur;
          tail->next = cur;
          cur->prev = tail;
      }
  }

  int pop_back(){
      int ans = tail->val;
      PNode p = tail->next;
      if (p != tail){
          tail = tail->prev;
          tail->next = p;
      }
      else tail = NULL;
      return ans;
  }

  int pop_front(){
      int ans = tail->next->val;
      if (tail->next != tail)tail->next = tail->next->next; else
          tail = NULL;
      return ans;
  }
};

Deque v[150000];

int main() {
  //FREOPEN("input.txt", "output.txt");
  int test,a,b;
  string s;
  scanf("%d\n", &test);
  while (test--){
      cin >> s;
      scanf("%d", &a);
      a--;
      if (s == "pushfront"){
          scanf("%d", &b);
          v[a].push_front(b);
      } else
      if (s == "pushback"){
          scanf("%d", &b);
          v[a].push_back(b);
      } else
      if (s == "popfront")printf("%d\n", v[a].pop_front()); else
      if (s == "popback") printf("%d\n", v[a].pop_back());
      scanf("\n");
  }
  return 0;
}