#include <iostream>
#include<fstream>
#include<vector>
#include<string>

using namespace std;
ifstream in("trie.in");
ofstream out("trie.out");



struct node
{
    char here;
    int endings;
    int occurences;
    node*node_list[26];
    node(char name)
    {
        endings=0;
        here=name;
        occurences=0;
        for(int i=0; i<26; i++)
            node_list[i]=nullptr;
    }
    ~node()
    {
        for(int i=0; i<26; i++)
            delete node_list[i];
    }
    bool contains(char to_check)
    {
        return node_list[to_check-'a']!=nullptr;
    }
    node*get_node(char name)
    {
        return node_list[name-'a'];
    }
    void add_node(char to_add)
    {
        node_list[to_add-'a']=new node(to_add);
    }
};

node base(' ');




void add_string(const std::string&to_add)
{
    node*here=&base;
    char c;
    for(int i=0; i<to_add.length(); i++)
    {
        c=to_add[i];
        if(!here->contains(c))
        {
            here->add_node(c);
        }
        here=here->get_node(c);
        here->occurences++;
    }
    here->endings++;


}





int get_ocurences(const std::string&to_check)
{
    node*here=&base;
    char c;
    for(int i=0; i<to_check.length(); i++)
    {
        c=to_check[i];
        if(!here->contains(c))
        {
            return 0;
        }
        here=here->get_node(c);
    }
    return here->endings;


}






int longest_prefix(const std::string&input)
{
    node*here=&base;
    char c;
    for(int i=0; i<input.length(); i++)
    {
        c=input[i];
        if(!here->contains(c))
        {
            return i;
        }
        here=here->get_node(c);
    }
    return input.length();
}





void erase_string(const std::string&to_check)
{
    node*here=&base;
    vector<node*> nodes;
    for(int i=0; i<to_check.length(); i++)
    {
        here=here->get_node(to_check[i]);
        here->occurences--;
        nodes.push_back(here);
    }
    here->endings--;




    node*last_node=&base;
    for(int i=0; i<nodes.size(); i++)
    {
        if(nodes[i]->occurences==0)
        {
            last_node->node_list[nodes[i]->here-'a']=nullptr;
            delete nodes[i];
            break;
        }
        last_node=nodes[i];


    }


}


void read()
{
    int query;
    string input;

    while(in>>query>>input)
    {
        if(query==0)
        {
            add_string(input);
        }
        else if(query==1)
        {
            erase_string(input);
        }
        else if(query==2)
        {
            out<<get_ocurences(input)<<'\n';
        }
        else
            out<<longest_prefix(input)<<'\n';



    }


}






int main()
{
    read();
    return 0;
}