#include <iostream>
#include <fstream>
#include <string.h>
#include <malloc.h>
using namespace std;
#define ios ios_base::sync_with_stdio(false);cin.tie(0);
#define setnow clock_t tStart;
#define setTime tStart = clock();
#define time0 (double)(clock() - tStart)/CLOCKS_PER_SEC
#define setin(x) ifstream cin(x);
#define setout(x) ofstream cout(x);
#define NMAX 30
typedef long long ll;
typedef long long int lli;
typedef pair < int, int> dbl;
const int maxInt = 1e9*2;
const lli maxLong = 1e18*2;

struct node{
    struct node *child[26];
    int words;
    node(){
        words = 0;
        for(int i=0;i<26;i++)child[i]=NULL;
    }
};

void insertWord(struct node *root, char* word){
    struct node *aux = root;
    int length = strlen(word);
    for(int i=0;i<length;i++){
        if(aux -> child[word[i]-'a'] == NULL){
            aux -> child[word[i]-'a'] = new node();
        }
        aux = aux -> child[word[i]-'a'];
    }
    aux->words++;
}

int haveChildren(struct node* root){
    for(int i=0;i<26;i++){
        if(root->child[i])
            return(1);
    }
    return(0);
}

int eraseWord(struct node* *root, char* word){
    if(*root == NULL)
        return(0);
    if(*word){
        if(*root != NULL && (*root)->child[*word - 'a'] != NULL &&
        eraseWord(&((*root)->child[*word-'a']), word + 1) && (*root) -> words == 0){
            if(!haveChildren(*root)){
                free(*root);
                (*root) = NULL;
                return(1);
            } else {
                return(0);
            }
        }
    }
    if(*word == '\0' && (*root)-> words == 1){
        if(!haveChildren(*root)){
            free(*root);
            (*root) = NULL;
            return(1);
        } else {
            (*root) -> words = 0;
            return(0);
        }
    }
    if(*word == '\0' && (*root)->words > 1){
        (*root)->words--;
        return(0);
    }
    return(0);
}

int findWord(struct node *root, char* word){
    struct node *aux = root;
    if(root == NULL)
        return(0);
    int length = strlen(word);
    for(int i=0;i<length;i++){
        if(aux -> child[word[i]-'a'] == NULL){
            return(0);
        }
        aux = aux -> child[word[i]-'a'];
    }
    if(aux && aux->words)
        return(aux->words);
    return(0);
}

int MaxPrefix(struct node *root, char* word){
    struct node *aux = root;
    int k = 0;
    int length = strlen(word);
    for(int i=0;i<length;i++){
        if(aux->child[word[i]-'a'])
            k++;
        else break;
        aux = aux -> child[word[i]-'a'];
    }
    return(k);
}

int main(){
    ios;
    setin("trie.in");
    setout("trie.out");
    int c;
    char str[50];
    node *root = new node();
    while(cin >> c >> str){
        if(c == 0){
            insertWord(root, str);
        }
        if(c == 1){
            eraseWord(&root, str);
        }
        if(c == 2){
            cout << findWord(root, str) << '\n';
        }
        if(c == 3){
            cout << MaxPrefix(root, str) << '\n';
        }
    }
}