#include <stdio.h>
#include <stdlib.h>
 
#define CH (*s - 'a')

struct TrieNode {
	struct TrieNode *parent;
	struct TrieNode *child[26];
	char childrenCount; // how many children it has - presumably useful for deletion
	short int freq; // nr of appearances of the word formed by the characters belonging to the path starting at root and ending here
};
typedef struct TrieNode TrieNode;

TrieNode mem[115000]; // chunk of 120000 nodes
int alloc_cnt = 1;
TrieNode *T = mem;  // first node in chunk we'll be using as root

/* 0 w - adauga o aparitie a cuvantului w in lista
1 w - sterge o aparitie a cuvantului w din lista
2 w - tipareste numarul de aparitii ale cuvantului w in lista
3 w - tipareste lungimea celui mai lung prefix comun al lui w cu oricare cuvant din lista

Pentru toate operatiile, cuvantul w este format din maxim 20 de caractere din intervalul 'a'..'z'
Numarul total de operatii nu va depasi 100 000
Operatiile de tip 1 w vor aparea numai daca w apare cel putin o data in lista de cuvinte */

void add(TrieNode *node, char *s) {  // assume word '\0' terminated
    char ch;
	while (1) {
		ch = *s - 'a';
		if (ch < 0) { // have hit either '\0' or '\n'
			node->freq++;
		    return;
		}
		if (node->child[ch] == NULL) {
		    node->child[ch] = &mem[alloc_cnt++];
		    node->child[ch]->parent = node;
		    node->childrenCount++;
	    }
		node = node->child[ch];
		s++;
	}
}

int rm(TrieNode *node, char *s) {
	char ch;
	while (1) {
		ch = *s++ - 'a';
		if (ch < 0) { // have hit either '\0' or '\n'
			node->freq--;
		    break;
		}
		node = node->child[ch];
	}
}

int query(TrieNode *node, char *s) {
	char ch;
	while (1) {
		ch = *s - 'a';
		if (ch < 0)
		    return node->freq;
		if (node->child[ch]) {
			node = node->child[ch];
			s++;
		}
		else
		    return 0;
	}
	return 0;
}

int prefix(TrieNode *node, char *s) {	short int t = 0;
    char ch;
	while (1) {
		ch = *s - 'a';
		if (ch < 0 || node->child[ch] == 0)
		    return t;
		if (node->child[ch]) {
			node = node->child[ch];
			s++;
			t++;
		}
	}
}

int main() {
	char line[32];
	char *s;
 
    freopen( "trie.in", "r", stdin );
	freopen( "trie.out", "w", stdout );
	//freopen( "grader_test20.in", "r", stdin );
	//freopen( "grader_test20.out", "w", stdout );
	fgets(line, 32, stdin);
 
	while(!feof(stdin)) {
		s = line+2;
		switch(line[0]) {
			case '0': add(T, s); 
			    break;
			case '1': rm(T, s); 
			    break;
			case '2': printf( "%d\n", query(T, s)); 
			    break;
			case '3': printf( "%d\n", prefix(T, s)); 
			    break;
		}
		fgets(line, 32, stdin);
	}
	//printf("alloc_cnt = %d\n", alloc_cnt);
	return 0;
}