#include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <queue>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <ctime>
#include <fstream>
#include <iterator>
#include <random>
#include <assert.h>
using namespace std;

const string file = "trie";

const string infile = file + ".in";
const string outfile = file + ".out";

const int INF = 0x3f3f3f3f; 

//#define ONLINE_JUDGE

struct Trie
{
    int wCount;
    int fCount;
    Trie* fii[26];

    Trie()
    {
        wCount = 0;
        fCount = 0;
        for(int i = 0; i < 26; i++)
            fii[i] = NULL;
    }
    ~Trie()
    {
        for(int i = 0; i < 26; i++)
        {
            if(fii[i] != NULL)
                delete fii[i];
        }
    }
};


void addW(Trie* root, string& w)
{
    int N = w.length();
    for(int i = 0; i < N; i++)
    {
        int c = w[i] - 'a';
        if(root->fii[c] == NULL)
        {
            root->fii[c] = new Trie();
            root->fCount++;
        }
        root = root->fii[c];
    }
    root->wCount++;
}
bool delW(Trie* root, string& w, int i)
{
    int N = w.length();
    if(i == N)
    {
        root->wCount --;
    }
    else
    {
        int c = w[i] - 'a';
        if(delW(root->fii[c], w, i + 1))
        {
            delete root->fii[c];
            root->fii[c] = NULL;
            root->fCount--;
        }
    }
    if(root->wCount == 0 && root->fCount == 0)
    {
        return true;
    }
    return false;
}

void delW(Trie* root, string& w)
{
    delW(root, w, 0);
}
int countW(Trie* root, string& w)
{
    int N = w.length();
    for(int i = 0; i < N; i++)
    {
        int c = w[i] - 'a';
        if(root->fii[c] == NULL)
        {
            return 0;
        }
        root = root->fii[c];
    }
    return root->wCount;
}
int prefixW(Trie* root, string& w)
{
    int N = w.length();
    for(int i = 0; i < N; i++)
    {
        int c = w[i] - 'a';
        if(root->fii[c] == NULL)
        {
            return i;
        }
        root = root->fii[c];
    }
    return N;
}

int main()
{
#ifdef ONLINE_JUDGE
	ostream &fout = cout;
	istream &fin = cin;
#else
	fstream fin(infile.c_str(), ios::in);
	fstream fout(outfile.c_str(), ios::out);
#endif	

    Trie* root = new Trie();
    int op;
    string w;
    while((fin >> op) && (fin >> w))
    {
        if(op == 0)
        {
            addW(root, w);
        }
        else if(op == 1)
        {
            delW(root, w);
        }
        else if(op == 2)
        {
            fout << countW(root, w) << "\n";
        }
        else if(op == 3)
        {
            fout << prefixW(root, w) << "\n";
        }
    }
    delete root;
#ifdef ONLINE_JUDGE
#else
    fout.close();
	fin.close();
#endif
}