#include <algorithm>
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#include <stack>

using namespace std;

#define pii pair <int, int>

string filename = "trie";

#ifdef LOCAL
    ifstream fin("input.in");
    ofstream fout("output.out");
#else
    ifstream fin(filename + ".in");
    ofstream fout(filename + ".out");
#endif

struct Trie{
    int f, cnt;
    Trie *nxt[26];

    Trie(){
        f = cnt = 0;
        for(int i = 0; i < 26; i++){
            nxt[i] = NULL;
        }
    }
};

Trie *root = new Trie;

int type;
string s;

void Insert(Trie *node, int ind){
    node->f++;
    if(ind == (int)s.size()){
        node->cnt++;
        return;
    }

    if(node->nxt[s[ind] - 'a'] == NULL){
        node->nxt[s[ind] - 'a'] = new Trie;
    }

    Insert(node->nxt[s[ind] - 'a'], ind + 1);
}

void Erase(Trie *node, int ind){
    node->f--;
    if(ind == (int)s.size()){
        node->cnt--;
    }else{
        Erase(node->nxt[s[ind] - 'a'], ind + 1);
        if(node->nxt[s[ind] - 'a']->f == 0){
            node->nxt[s[ind] - 'a'] = NULL;
        }
    }
}

int query1(Trie *node, int ind){
    if(ind == (int)s.size()){
        return node->cnt;
    }

    if(node->nxt[s[ind] - 'a'] == NULL){
        return 0;
    }
    return query1(node->nxt[s[ind] - 'a'], ind + 1);
}

int query2(Trie *node, int ind){
    if(ind == (int)s.size()){
        return ind;
    }

    if(node->nxt[s[ind] - 'a'] == NULL){
        return ind;
    }

    return query2(node->nxt[s[ind] - 'a'], ind + 1);
}

int main(){

    while(fin >> type >> s){
        if(type == 0){
            Insert(root, 0);
        }else if(type == 1){
            Erase(root, 0);
        }else if(type == 2){
            fout << query1(root, 0) << '\n';
        }else{
            fout << query2(root, 0) << '\n';
        }
    }

    return 0;
}