#include <iostream>
#define endl '\n';
using namespace std;


struct bst{
    string nome;
    bst* left;
    bst* right;
    bst* up;
    bst* down;
    bool isDirectory;

    void setRoot(){
        this->nome = "/";
        this->up = nullptr;
        this->down = nullptr;
        this->left = nullptr;
        this->right = nullptr;
        isDirectory = true;
    }
};

bst *touch(bst *root, bst* up, string nome){
    if(root == nullptr){
        bst *n = new bst;
        n->nome = nome;
        n->left = nullptr;
        n->right = nullptr;
        n->down = nullptr;
        n->up = up;
        n->isDirectory = false;
        return n;
    }else if(nome < root->nome){
        root->left = touch(root->left, up,nome);
        return root;
    }else{
        root->right = touch(root->right,up,nome);
        return root;
    }
}

bst *mkdir(bst *root, bst* up, string nome){
    if(root == nullptr){
        bst *n = new bst;
        n->nome = nome;
        n->left = nullptr;
        n->right = nullptr;
        n->down = nullptr;
        n->up = up;
        n->isDirectory = true;
        return n;
    }else if(nome < root->nome){
        root->left = mkdir(root->left, up,nome);
        return root;
    }else{
        root->right = mkdir(root->right,up,nome);
        return root;
    }
}

string pwd(bst *root){
    return root->nome;
}

string pre_order(bst* root, string indentacao){
    if(root == nullptr || root->up == nullptr){
        return "";
    }
    cout << indentacao << root->nome << endl;
    if(root->isDirectory ){
        pre_order(root->down, indentacao+"    ");
    }
    pre_order(root->left,indentacao);
    pre_order(root->right,indentacao);
}

string in_order(bst* root, string indentacao){
    if(root == nullptr || root->up == nullptr){
        return "";
    }
    in_order(root->left, indentacao);
    cout << indentacao << root->nome << endl;
    if(root->isDirectory ){
        indentacao += "    ";
        in_order(root->down, indentacao);
        indentacao = "";
    }
    in_order(root->right,indentacao);
}

string pos_order(bst* root, string indentacao){
    if(root == nullptr || root->up == nullptr){
        return "";
    }
    pos_order(root->left,indentacao);
    pos_order(root->right,indentacao);
    cout << indentacao << root->nome << endl;
    if(root->isDirectory ){
        pos_order(root->down, indentacao+"    ");
    }
}

string ls(bst* root){
    if(root == nullptr || root->up == nullptr){
        return "";
    }
    ls(root->left);
    cout << root->nome << endl;
    ls(root->right);
}

int busca_previa(bst *root, string nome){
    if(root == nullptr){
        return 0;
    }else if(nome == root->nome){
        if(root->isDirectory){
            return 1;
        }
        return 2;
    }else if(nome < root->nome){
        return busca_previa(root->left, nome);
    }else{
        return busca_previa(root->right,nome);
    }
}

bst* cd(bst* root, string nome){

    if(root == nullptr){
        return nullptr ;
    }else if(nome == root->nome){
        return root;
    }else if(nome < root->nome){
        return cd(root->left, nome);
    }else{
        return cd(root->right,nome);
    }
}
struct bst_min{
    bst* root;
    string nome;
};

bst_min* bst_delete_min(bst* root){
    if(root->left == nullptr){
        bst_min* opa = new bst_min;
        opa->nome = root->nome;
        opa->root = root->right;
        delete root;
        return opa;
    }else{
        bst_min* rm = bst_delete_min(root -> left);
        root->left = rm->root;
        root->nome = rm->nome;
        return rm;
    }

}

bst* rm(bst* root, string nome){
    if(root == nullptr){
        cout << "No such file or directory" << endl;
        return nullptr;
    }else if(nome < root->nome){
        root->left = rm(root->left,nome);
        return root;
    }else if(nome > root->nome){
        root->right = rm(root->right,nome);
        return root;
    }else{
        if(root->left == nullptr){
            bst* r = root->right;
            delete root;
            return r;
        }else if(root->right == nullptr){
            bst* l = root->left;
            delete root;
            return l;
        }else{
            bst_min* rm = bst_delete_min(root -> right);
            root->right = rm->root;
            root->nome = rm->nome;
            return root;
        }
    }

}




int main(){
    bst *pimba = new bst;
    pimba->setRoot();
    bst* current = pimba;
//    string indentacao = "";
//
//    cout << pwd(current) << endl;
//    current->down = mkdir(current->down,current,"Q");
//    current->down = mkdir(current->down,current,"A");
//    current->down = mkdir(current->down,current,"Z");
//    current = cd(current->down, "A");
//    current->down = touch(current->down,current, "W");
//    current->down = mkdir(current->down,current, "S");
//    current->down = touch(current->down,current, "X");
//    current = cd(current->down, "S");
//    current->down = touch(current->down,current, "1");
//    current->down = touch(current->down,current, "0");
//    current->down = touch(current->down,current, "2");
//    current->down = touch(current->down,current, "9");
//    current = current->up;
//    if(busca_previa(current->down,"P") == 0){
//        cout << "No such file or directory" << endl;
//    }else if(busca_previa(current->down, "P") == 2){
//        cout << "Not a directory" << endl;
//    }else if(busca_previa(current->down,"P") == 1){
//        current = cd(current->down,"P");
//    }
//    ls(current->down);
//    if(busca_previa(current->down,"X") != 0){
//        cout << "File exists" << endl;
//            }else{
//        current->down = mkdir(current->down,current,"X");
//    }
//    current = current->up;
//    current = cd(current->down, "Q");
//    current->down = touch(current->down,current, "E");
//    current->down = touch(current->down,current, "D");
//    current = current->up;
//    current = cd(current->down, "Z");
//    current->down = touch(current->down, current, "X");
//    current = current->up;
//    in_order(current->down,indentacao);

    string comando;
    string d;

    while(cin >> comando){
        string indentacao;
        if(comando == "cd"){
            cin >> d;
            if(d == ".."){
                if(current->up != nullptr){
                    current = current->up;
                }
            }else{
                if(busca_previa(current->down,d) == 0){
                    cout << "No such file or directory" << endl;
                }else if(busca_previa(current->down, d) == 2){
                    cout << "Not a directory" << endl;
                }else if(busca_previa(current->down,d) == 1){
                    current = cd(current->down,d);
                }
            }

        }else if(comando == "ls"){
            ls(current->down);

        }else if(comando == "touch"){
            string f;
            cin >> f;
            if(busca_previa(current->down,f) != 0){
                cout << "File exists" << endl;
            }else{
                current->down = touch(current->down,current,f);
            }

        }else if(comando == "mkdir"){
            string nD;
            cin >> nD;
            if(busca_previa(current->down,nD) != 0){
                cout << "File exists" << endl;
            }else{
                current->down = mkdir(current->down,current,nD);
            }

        }else if(comando == "pwd"){
            cout << pwd(current) << endl;

        }else if(comando == "tree"){
            string arg;
            cin >> arg;
            if(arg == "--pre-order"){
                pre_order(current->down,indentacao);

            }else if(arg == "--in-order"){
                in_order(current->down,indentacao);

            }else if(arg == "--post-order"){
                pos_order(current->down,indentacao);

            }else{
                cout << "Illegal option" << endl;
            }

        }else if(comando == "rm"){
            string f;
            cin >> f;
            current->down = rm(current,f);

        }else{
            cout << "Command not found" << endl;
        }

    }

    return 0;
}