#include <iostream>
#include <stdio.h>
#include <cstring>
#include <fstream>
#define trie node*
using namespace std;

typedef struct node{
    int nrCuv;
    trie nextT[26];
    int nrPr;
            
} node;

trie T;

trie createT() {
     trie tr = new node();
     tr->nrCuv = 0;   
     tr->nrPr = 0; 
     memset(tr->nextT, 0, 26 * sizeof(trie)); 
     return tr;
}

void add_(string word) {
     trie R = T;
     int i = 0;
     while (i < word.length()) {
         int poz = word[i] - 'a';
         if (T->nextT[poz] == NULL) {
             T->nextT[poz] = createT();                        
         }
         T = T->nextT[poz];         
         if (i == word.length() - 1) {
             T->nrCuv++;   
         }         
         T->nrPr++;
         i++;            
     }
     T = R;
}

void del_(string word) {
     trie R = T;
     int i = 0;
     while (i < word.length()) {
         int poz = word[i] - 'a';
         T = T->nextT[poz];
         if (i == word.length() - 1) {
             T->nrCuv--;   
         }         
         T->nrPr--;
         i++;            
     }
     T = R;
}

void print_nrCuv(string word) {
     trie R = T;
     int i = 0;
     while (i < word.length() && T->nextT[word[i] - 'a'] != NULL) {
         int poz = word[i] - 'a';
         T = T->nextT[poz];
         i++;            
     }     
     printf("%d\n", T->nrCuv);
     T = R;
}

void print_pref(string word) {
     trie R = T;
     int i = 0;
     int lmax = 0;
     while (i < word.length() && T->nextT[word[i] - 'a'] != NULL) {
         int poz = word[i] - 'a';
         T = T->nextT[poz];       
         i++;
         if (T->nrPr > 0) {
            lmax = i;            
         }
     }  
     printf("%d\n", lmax); 
     T = R;
}

// Functie suplimentara pentru afisarea trie-ului
void print_trie(trie tr, int poz, char c) {
     for (int i = 0; i <= poz; i++) {printf(" ");}
     printf("%d %c\n", tr->nrCuv, c);
     for (int i = 0; i <= 25; i++) {
         if (tr->nextT[i] != NULL) {
            print_trie(tr->nextT[i], poz + 1, i + 'a');              
         }
     }
}

// Functie suplimentara pentru afisarea trie-ului
void print_tr(string word) {
      cout<< "word: " << word << endl;
      printf("trie:\n");
      print_trie(T, 0, '#');
}     

void read_() {
     ifstream in("trie.in");
     while (!in.eof()) {
           string word;
           int op;           
           in >> op >> word;
           switch (op) {
               case 0: 
                    add_(word);                  
                    //printf("\nadd:\n");print_tr(word);
                    break;
               case 1: 
                    del_(word);
                    //printf("\ndell:\n");print_tr(word);
                    break;
               case 2:
                    print_nrCuv(word);
                    break;
               case 3: 
                    print_pref(word);
                    break;
               default:
                    break;          
           }                      
     }     
}

void init_() {
     T = createT();     
}

int main() {
    freopen("trie.in", "r", stdin);
    freopen("trie.out", "w", stdout);
    
    init_();
    read_();
    
    return 0;
}