#include <fstream>
#include <string>
#include <stdlib.h>
 
#define max 26
#define word[index]-'a' CH
#define MAX 100000
 
using namespace std;
 
ifstream fin("trie.in");
ofstream fout("trie.out");
 
struct Trie{
    int pass; // how many nodes pass through this node 
    int appear; // how many nodes end here
    struct Trie *refs[max];
};
 
typedef struct Trie Trie;
 
Trie root;
 
void addWord(string word){
    int index = 0, len = word.size();
    Trie *t = &root;
	t->pass ++;
    while(index < len){
        if(t->refs[word[index]-'a'] == NULL){
            Trie *nou = (Trie*)malloc(1*sizeof(Trie));
            nou->pass = 1;
            nou->appear = 0;
            for(int i = 0; i < max; i++)
                nou->refs[i] = NULL;
            t->refs[word[index]-'a'] = nou;
        }else{
            t->refs[word[index]-'a']->pass++;
        }
         
        // sets final node
        if(index == len-1){
            t->refs[word[index]-'a']->appear ++;
        }
        t = t->refs[word[index]-'a'];
        index ++;
    }
}
 
int inline printHowMany(string word, int index, Trie *t){
    /*Trie *t = &root;
    int index = 0, len = word.size();
    while(index < len && t != NULL){
        t = t->refs[CH];
        index ++;
    }
    if(index == len && t != NULL){
        return t->appear;
    }*/
	if(t->refs[word[index]-'a'] == NULL)
		return 0;
	if(index == word.size()-1)
		return t->appear;
	printHowMany(word, index+1, t->refs[word[index]-'a']);
		
}
 
void deleteWord(string word){
    Trie *t = &root, *next;
    int index = 0, len = word.size();
    if(printHowMany(word) == 0) return ;
    while(index < len){
        if(t->refs[word[index]-'a']->pass == 1){
            if(t->refs[word[index]-'a']->appear > 0){
                free(t->refs[word[index]-'a']);
                t->refs[word[index]-'a'] = NULL;
            }else{
                for(int i = 0; i < 26; i++){
                    if(t->refs[word[index]-'a']->refs[i] != NULL){
                        next = t->refs[word[index]-'a']->refs[i];
                        free(t->refs[word[index]-'a']);
                        t->refs[word[index]-'a'] = NULL;
                        t->refs[i] = next;
                        break;
                    }
                }
            }
        }else{
            t->refs[word[index]-'a']->pass--;
            if(index == len-1){
                t->refs[word[index]-'a']->appear--;
            }
            t = t->refs[word[index]-'a'];
        }
        index++;
    }
}
 
int printPrefix(string prefix){
    Trie *t = &root;
    int len = prefix.size(), index = 0, maxim = 0;
    while(index < len){
        if(t->refs[prefix[index] - 'a'] != NULL){
                t = t->refs[prefix[index] - 'a'];
                maxim++;
        }else{
            break;
        }
        index++;
    }
    return maxim;
}
 
void process(int which, string word){
	Trie *t = &root;
    switch(which){
    case 0: addWord(word); break;
    case 1: deleteWord(word); break;
    case 2: fout << printHowMany(word,0,t) << "\n"; break;
    case 3: fout << printPrefix(word) << "\n";
    }
}
 
int main(){
    int which, i;
    string word;
 
    root.appear = 0;
    root.pass = 0;   // passul asta nu are relevanta pt root 
    for(int i = 0; i < max; i++)
        root.refs[i] = NULL;
 
    while(fin >> which >> word){
        process(which, word);
    }
    return 0;
}