#include<bits/stdc++.h>

using namespace std;

template <class T>
class LinkedList{
public:
        virtual void push_back(T val) = 0;
        virtual void push_front(T val) = 0;
        virtual int size() = 0;
        virtual bool isempty() = 0;
        virtual void clear() = 0;
        virtual T back() = 0;
        virtual T front() = 0;
        virtual T pop_front() = 0;
        virtual void pop_back() = 0;
        virtual T get(int index) = 0;
};

template<class K>
class Node{
public:
        K value;
        Node* next = nullptr;
        Node* previus = nullptr;
        Node(K value){
                this->value = value;
        }
};

template<class T>
class DoubleLinkedList : public LinkedList<T>{

int length = 0;
Node<T>* head = nullptr;
Node<T>* tail = nullptr;

public:
        void push_back(T val) override
        {
                Node<T>* new_val = (new Node<T>(val));
                if(length == 0){
                        head = new_val;
                        tail = new_val;
                }else{
                        auto x = head;
                        head = new_val;
                        new_val = x;
                        new_val->next = head;
                        head->previus = new_val;
                }
                length++;
        }

        void push_front(T val)override
        {
                auto new_val = new Node<T>(val);
                if(length == 0){
                        head = new_val;
                        tail = new_val;
                }else{
                        auto x = tail;
                        tail = new_val;
                        new_val = x;
                        new_val->previus = tail;
                        tail->next = new_val;
                }
                length++;
        }

        int size() override
        {
                return length;
        }

        bool isempty()override
        {
                return (length == 0);
        }

        void clear()override
        {
                length = 0;
                delete tail->next;
                delete tail->previus;
                delete head->next;
                delete head->previus;
                head = nullptr;
                tail = nullptr;
        }

        T front()override
        {
                assert(tail != nullptr);
                return tail->value;
        }

        T back()override
        {
                assert(head != nullptr);
                return head->value;
        }

        T pop_front()override
        {
                if(isempty()){
                        throw std::runtime_error("eee be ota list kholihay, kjo pop_front() mekni");
                }
                T res = tail->value;
                if(tail->next != nullptr){
                        assert(tail->next != nullptr);
                        auto x = tail;
                        tail = tail->next;
                        tail->previus = nullptr;
                        delete x;
                }else{
                        delete tail->next;
                        delete tail->previus;
                        delete head->next;
                        delete head->previus;
                        tail = nullptr;
                        head = nullptr;
                }
                length--;
                return res;
        }

        void pop_back()override
        {
                if(length == 0){
                        throw std::runtime_error("eee be ota list kholihay, kjo pop_back() mekni");
                }
                else if(head->previus == nullptr){
                        delete tail->next;
                        delete tail->previus;
                        delete head->next;
                        delete head->previus;
                        tail = nullptr;
                        head = nullptr;
                }else{
                        assert(head->previus != nullptr);
                        auto x = head;
                        head = head->previus;
                        head->next = nullptr;
                        delete x;
                }
                length--;
        }
        virtual T get(int index){
                if(index < 0 || index >= length){
                    throw std::runtime_error("out of bounded array index");
                }else{
                    Node<T>* current_node = tail;
                    for(int i = 0; i < index; i ++){
                        current_node = current_node->next;
                    }
                    return current_node->value;
                }
            }
};

template<class T>
class ICircularBoundedQueue
{
        public:
        virtual void offer(T value) = 0;
        // insert an element to the rear of the queue
        // overwrite the oldest elements
        // when the queue is full
        virtual T poll() = 0;// remove an element from the front of the queue and return removed element
        virtual T peek() = 0;// look at the element at the front of the queue
        // (without removing it)
        virtual void flush() = 0;// remove all elements from the queue
        virtual bool isEmpty() = 0;// is the queue empty?
        virtual bool isFull() = 0;// is the queue full?
        virtual int size() = 0;// number of elements
        virtual int capacity() = 0;// maximum capacity
};

template <class T>
class CircularBoundedQueue : public ICircularBoundedQueue<T>{

        DoubleLinkedList <T> q;
        int Capacity;
public:
        CircularBoundedQueue(int C=100) : Capacity(C){}
        void init(int C)
        {
                Capacity = C;
        }
        virtual void offer(T new_variable)override
        {
                if(q.size() >= capacity()){
                        auto x = q.front();
                        q.pop_front();
                        delete[] x.first.a;
                        delete[] x.first.b;
                        delete[] x.second.a;
                        delete[] x.second.b;
                }
                q.push_back(new_variable);
        }

        virtual T poll()override
        {
                T x = q.front();
                q.pop_front();
                return x;
        }

        virtual T peek()override
        {
                return q.front();
        }

        virtual void flush()override
        {
                q.clear();
        }

        virtual bool isFull() override
        {
                return (q.size() == capacity());
        }

        virtual bool isEmpty() override
        {
                return q.isempty();
        }

        virtual int size() override
        {
                return q.size();
        }

        virtual int capacity() override
        {
                return Capacity;
        }

};


template<class T>
class Stack{
        virtual void push(T value) = 0;// push an element onto the stack
                                        // remove the oldest element
                                        // when if stack is full
        virtual T pop() = 0;    // remove an element from the top of the stack
        virtual T top() = 0;    // look at the element at the top of the stack
                                // (without removing it)
        virtual void flush() = 0;// remove all elements from the stack
        virtual bool isEmpty() = 0;// is the stack empty?
        virtual bool isFull() = 0;// is the stack full?
        virtual int size() = 0; // number of elements
        virtual int capacity() = 0; // maximum capacity
};

template<class T>
class BoundedStack : public Stack<T>{
        CircularBoundedQueue<T> q1;
        CircularBoundedQueue<T> q2;
        int Capacity;
public:
        void init(int val){
                Capacity = val;
                q1.init(val);
                q2.init(val);
        }

        void push(T value) override
        {
                if(q1.isEmpty()){
                        q1.offer(value);
                }else{
                        if(q1.size() == capacity()){
                                while(!q1.isEmpty()){
                                        if(q1.size() == 1){
                                                auto x = q1.peek();
                                                q1.poll();
                                                delete[] x.first.a;
                                                delete[] x.first.b;
                                                delete[] x.second.a;
                                                delete[] x.second.b;
                                                break;
                                        }
                                        q2.offer(q1.poll());
                                }
                        }else{
                                while(!q1.isEmpty()){
                                        q2.offer(q1.poll());
                                }
                        }
                        q1.offer(value);
                        while(!q2.isEmpty()){
                                q1.offer(q2.poll());
                        }
                }
        }

        int capacity()override
        {
            return Capacity;
        }

        T pop()override
        {
                return q1.poll();
        }

        T top()override
        {
                assert(!q1.isEmpty());
                return q1.peek();
        }

        void flush()override
        {
                while(!q1.isEmpty()){
                        q1.poll();
                }
        }

        int size()override
        {
                return q1.size();
        }

        bool isEmpty()override
        {
                return (q1.size() == 0);
        }

        bool isFull() override
        {
                return (q1.size() == capacity());
        }
};

template<class T>
class Iset{
        virtual void add(T item) = 0; // add item in the set
        virtual void remove(T item) = 0; // remove an item from a set
        virtual bool contains(T item) = 0; // check if a item belongs to a set
        virtual int size() = 0; // number of elements in a set
        virtual bool isEmpty() = 0; // check if the set is empty
};

template <class T>
class DoubleHasSet : public Iset<T>{
public:
        int* a;
        T* b;
        int length = 0;
        int Capacity = 2;
        DoubleHasSet()
        {
                Capacity = 2;
                a = new int[2];
                b = new T[2];
                a[0] = a[1] = 0;
                length = 0;
        }

        int getHash(T key, int j)
        {
                auto hashfunc = std::hash<T>();
                int val = hashfunc(key);
                val = abs(val);
                int res = val % capacity();
                res += j;
                res %= capacity();
                if(res < 0)res += capacity();
                return res;
        }

        void resize()
        {
                int old_capacity = capacity();
                Capacity *= 2;
                auto x = b;
                auto y = a;
                b = new T[Capacity];
                a = new int[Capacity];
                for(int i = 0; i < Capacity; i++){
                        a[i] = 0;
                }
                length = 0;
                for(int i = 0; i < old_capacity; i++){
                        if(y[i] == 1){
                                add(x[i]);
                        }
                }
                delete[] x;
                delete[] y;
        }

        void add(T item) override
        {
                if(capacity() == size()){
                        resize();
                }
                if(contains(item))return;
                int j = 0;
                while(j <= capacity() && a[getHash(item, j)] == 1){
                        j++;
                }
                if(a[getHash(item, j)] == 1){
                        throw runtime_error("You can not add new element, because of capacity");
                }
                a[getHash(item, j)] = 1;
                b[getHash(item, j)] = item;
                length++;
        }

        bool contains(T item)override
        {
                int j = 0;
                while(j <= capacity() && a[getHash(item, j)] != 0){
                        if(a[getHash(item, j)] == 1 && b[getHash(item, j)] == item){
                                return true;
                        }
                        j++;
                }
                return false;
        }

        void remove(T item)override
        {
                int j = 0;
                while(j <= capacity() && a[getHash(item, j)] != 0){
                        if(a[getHash(item, j)] == 1 && b[getHash(item, j)] == item){
                                a[getHash(item, j)] = 2;
                                length--;
                                break;
                        }
                        j++;
                }
        }

        int size()override
        {
                return length;
        }

        bool isEmpty()override
        {
                return size() == 0;
        }

        int capacity()
        {
                return Capacity;
        }
};



int main()
{
        //freopen("input.txt", "r", stdin);
        string A;
        int n,k;
        cin >> n >> k;
        BoundedStack<pair<DoubleHasSet<string>, DoubleHasSet<string>>> st;
        getline(cin, A);
        st.init(k);
        DoubleHasSet<string> a,b;
        st.push({a, b});// empty set
        while(n--){
                getline(cin, A);
                string s = "",t = "";
                for(int i = 0, j = 0; i < (int)A.size(); i++){
                        if(A[i] == ' '){
                                if(j == 1){
                                        s = "N";
                                        break;
                                }
                                j = 1;
                        }else if(j){
                                t += A[i];
                        }else{
                                s += A[i];
                        }
                }
                if(s == "NEW"){
                        auto File = st.top().first;
                        auto Directory = st.top().second;
                        auto x = new int[File.capacity()];
                        auto y = new string[File.capacity()];
                        for(int i = 0; i < File.capacity(); i++){
                                x[i] = File.a[i];
                                y[i] = File.b[i];
                        }
                        auto xx = new int[Directory.capacity()];
                        auto yy = new string[Directory.capacity()];
                        for(int i = 0; i < Directory.capacity(); i++){
                                xx[i] = Directory.a[i];
                                yy[i] = Directory.b[i];
                        }
                        File.a = x;
                        File.b = y;
                        Directory.a = xx;
                        Directory.b = yy;
                        if(t.back() == '/'){
                                t.pop_back();
                                if(Directory.contains(t) || File.contains(t)){
                                        cout << "ERROR: cannot execute " << A << endl;
                                        continue;
                                }
                                Directory.add(t);
                        }else{
                               if(Directory.contains(t) || File.contains(t)){
                                        cout << "ERROR: cannot execute " << A << endl;
                                        continue;
                                }
                                File.add(t);
                        }
                        st.push({File, Directory});
                }else if(s == "REMOVE"){
                        auto File = st.top().first;
                        auto Directory = st.top().second;
                        auto x = new int[File.capacity()];
                        auto y = new string[File.capacity()];
                        for(int i = 0; i < File.capacity(); i++){
                                x[i] = File.a[i];
                                y[i] = File.b[i];
                        }
                        auto xx = new int[Directory.capacity()];
                        auto yy = new string[Directory.capacity()];
                        for(int i = 0; i < Directory.capacity(); i++){
                                xx[i] = Directory.a[i];
                                yy[i] = Directory.b[i];
                        }
                        File.a = x;
                        File.b = y;
                        Directory.a = xx;
                        Directory.b = yy;
                        if(t.back() == '/'){
                                t.pop_back();
                                if(!Directory.contains(t)){
                                        cout << "ERROR: cannot execute " << A << endl;
                                        continue;
                                }
                                Directory.remove(t);
                        }else{
                               if(!File.contains(t)){
                                        cout << "ERROR: cannot execute " << A << endl;
                                        continue;
                                }
                                File.remove(t);
                        }
                        st.push({File, Directory});
                }else if(s == "UNDO"){
                        int n1 = 1;
                        bool f = false;
                        if((int)t.size() > 0){
                                n1 = 0;
                                for(int i = 0; i < (int)t.size(); i++){
                                        if(!('0' <= t[i] && t[i] <= '9')){
                                                cout << "ERROR: cannot execute " << A << endl;
                                                f = true;
                                                break;
                                        }
                                        n1 *= 10;
                                        n1 += t[i] - '0';
                                }
                        }
                        if(f)continue;
                        if(n1 >= st.size()){
                                cout << "ERROR: cannot execute " << A << endl;
                                continue;
                        }
                        for(int i = 1; i <= n1; i++){
                                delete[] st.top().first.a;
                                delete[] st.top().first.b;
                                delete[] st.top().second.a;
                                delete[] st.top().second.b;
                                st.pop();
                        }
                }else if(s == "LIST"){
                        auto File = st.top().first;
                        auto Directory = st.top().second;
                        for(int i = 0; i < File.capacity(); i++){
                                if(File.a[i] == 1){
                                        cout << File.b[i] << " ";
                                }
                        }
                        for(int i = 0; i < Directory.capacity(); i++){
                                if(Directory.a[i] == 1){
                                        cout << Directory.b[i] << "/ ";
                                }
                        }
                        cout << endl;
                }else{
                        cout << "ERROR: cannot execute " << A << endl;
                }
        }
}