#include <iostream>
#include <fstream>
#include <cstring>

using namespace std;

#define CH (*s - 'a')

// Trie structure
struct Trie {
    int cnt, numberOfChildren;    
    Trie *child[26];     

    Trie() {
        cnt = numberOfChildren = 0;
        memset(child, 0, sizeof(child));
    }
};


Trie *T = new Trie;


void ins(Trie *nod, const char *s) {
    while (*s != '\0') {  
        if (nod->child[CH] == 0) {  
            nod->child[CH] = new Trie;
            nod->numberOfChildren++;
        }
        nod = nod->child[CH];
        s++;  
    }
    nod->cnt++;  
}



int del(Trie *nod, const char *s) {
    if (*s == '\0') {  
        nod->cnt--;
    } else if (del(nod->child[CH], s + 1)) {  
        nod->child[CH] = 0; 
        nod->numberOfChildren--;
    }


    if (nod->cnt == 0 && nod->numberOfChildren == 0 && nod != T) {
        delete nod;
        return 1;  
    }
    return 0;
}


int que(Trie *nod, const char *s) {
    if (*s == '\0') {  
        return nod->cnt;
    }

    if (nod->child[CH]) {  
        return que(nod->child[CH], s + 1);
    }
    return 0;  
}


int pre(Trie *nod, const char *s, int k) {
    while (*s != '\0') {
        if (nod->child[CH] == 0) break;  
        nod = nod->child[CH];
        s++;
        k++;  
    }
    return k;
}

int main() {
    ifstream in ("trie.in");
    ofstream out ("trie.out");
    char operation;
    string word;

    while (in >> operation >> word) {
        switch (operation) {
            case '0': 
                ins(T, word.c_str());
                break;
            case '1': 
                del(T, word.c_str());
                break;
            case '2': 
                out << que(T, word.c_str()) << '\n';
                break;
            case '3': 
                out << pre(T, word.c_str(), 0) << '\n';
                break;
        }
    }

    return 0;
}