#include <iostream>
#include <string>
using namespace std;

class Account{
    public:
      string employee;
      string class_room;
      string combined(){
          return class_room+employee;
      }
};

class myvector{
    private:

    public:
      Account *employees;
      int size;
        myvector(){
            size=0;
            employees=new Account[size];
        }

        ~myvector(){
            delete[] employees;
        }

        void push(string name, string room){
            size++;
            Account *array=new Account[size];

            for(int i=0; i<size-1; i++){
                array[i] = employees[i];
            }

            Account *newaccount=new Account;
            newaccount->employee=name;
            newaccount->class_room=room;
            array[size-1]= *newaccount;
            delete[] employees;
            employees = array;

        }
        Account at(int index){
            return employees[index];
        }
        int lenght(){
            return size;
        }
        int search(string name){
            for(int i=0; i<size; i++){
                if(employees[i].employee==name){
                    return i;
                }
            }
            return -1;
        }
        void erase(string name){
            employees[search(name)]=employees[size-1];
            Account *array=new Account[size-1];
            for(int i=0; i<size-1; i++){
                if(employees[i].employee!=name){
                    array[i] = employees[i];
                  }
            }
            delete[] employees;
            employees = array;
            size--;
        }
        void clear(){
            delete[] employees;
            size=0;
            Account *employees=new Account[size];
        }
        void sort(){
            bool isUnsorted=true;
            int sequence_count=1;
            while(isUnsorted){
                isUnsorted=false;
                for(int i=0; i<size-sequence_count; i++){
                    if((employees[i].combined().compare(employees[i+1].combined()))==1){
                        isUnsorted=true;
                        Account token=employees[i];
                        employees[i]=employees[i+1];
                        employees[i+1]=token;
                    }
                }
                sequence_count++;
            }
        }
};

class AddressBook{
    private:
        myvector accounts;
    public:
        void add(string name, string room){
            if(accounts.search(name)!=-1){
                throw runtime_error("Account already exists");
            }
            accounts.push(name, room);
        }
        void move(string name, string room){
            if(accounts.search(name)==-1){
                throw runtime_error("Account does not exists");
            }
            accounts.erase(name);
            accounts.push(name, room);
        }
        void removal(string name){
            if(accounts.search(name)==-1){
                throw runtime_error("Account does not exists");
              }
            accounts.erase(name);
        }
        void find(string name){
            if(accounts.search(name)==-1){
                throw runtime_error("Account does not exists");
            }
            cout << accounts.at(accounts.search(name)).employee << " is in room " << accounts.at(accounts.search(name)).class_room << endl;
        }
        void list(){
            if(accounts.lenght()<1){
                throw runtime_error("List is empty");
            }
            accounts.sort();
            for(int i=0; i<accounts.lenght(); i++){
                cout << accounts.at(i).employee << " is in room " << accounts.at(i).class_room << endl;
            }
        }
        void clear(){
            accounts.clear();
        }
};
void room_check(string room){
    if(room.size()!=4){
        throw runtime_error("Invalid room code");
    }
    if(!isalpha(room[0])){
        throw runtime_error("Invalid room code");
    }
    for(int i=1; i<4; i++){
        if(!isdigit(room[i])){
            throw runtime_error("Invalid room code");
        }
    }
}

int main(){
    string command;
    string name;
    string room;
    AddressBook book;
    while (true){
        try{
            cin >> command;
            if (command=="add"||command=="move"||command=="remove"||command=="find"){
                cin >> name;
                if(command=="add"||command=="move"){
                    cin >> room;
                }
            }

            if(command=="add"){
                room_check(room);
                book.add(name, room);
            }
            if(command=="move"){
                room_check(room);
                book.move(name, room);
            }
            if(command=="remove"){
                book.removal(name);
            }
            if(command=="find"){
                book.find(name);
            }
            if(command=="list"){
                book.list();
            }
            if(command=="clear"){
                book.clear();
            }
            if(command=="exit"){
                return 0;
            }
        }
        catch (runtime_error &e){
            cerr << "Error: " <<e.what() << endl;
        }
    }
    return 0;
}