/// left-child right-sibling tree, memorie alocata dinamic

#include <iostream>
#include <cstdio>
#include <cstring>

using namespace std;

const int LMAX = 20;
const int SIGMA = 3;
const int NROP = 100000;

struct nod {
  char ch;
  int nr_ap, capat;
  nod *child, *sibling;

  nod(char _ch = '*') : ch(_ch), nr_ap(0), capat(0), child(0), sibling(0) {}
};

void add_cuv(nod *root, char *cuv, int l) {
  root->nr_ap++;
  if(l == 0)
    root->capat++;
  else {
    nod *last_child = 0;
    for(nod *child = root->child; child; child = child->sibling) {
      last_child = child;
      if(child->ch == cuv[0]) {
        add_cuv(child, cuv + 1, l - 1);
        return;
      }
    }

    if(!last_child) {
      root->child = new nod(cuv[0]);
      add_cuv(root->child, cuv + 1, l - 1);
    }
    else {
      last_child->sibling = new nod(cuv[0]);
      add_cuv(last_child->sibling, cuv + 1, l - 1);
    }
  }
}

void del_cuv(nod *root, char *cuv, int l) {
  root->nr_ap--;
  if(l == 0)
    root->capat--;
  else {
    nod *prev = root;
    for(nod *child = root->child; child; prev = child, child = child->sibling)
      if(child->ch == cuv[0]) {
        del_cuv(child, cuv + 1, l - 1);

        if(child->nr_ap == 0) {
          if(prev == root)
            prev->child = child->sibling;
          else
            prev->sibling = child->sibling;
          delete child;
        }
        return;
      }
  }
}

int get_nr_ap(nod *root, char *cuv, int l) {
  if(l == 0)
    return root->capat;
  for(nod *child = root->child; child; child = child->sibling)
    if(child->ch == cuv[0])
      return get_nr_ap(child, cuv + 1, l - 1);
  return 0;
}

int get_longest_prefix(nod *root, char *cuv, int l) {
  if(l == 0)
    return 0;
  for(nod *child = root->child; child; child = child->sibling)
    if(child->ch == cuv[0])
      return 1 + get_longest_prefix(child, cuv + 1, l - 1);
  return 0;
}

int main() {
  freopen("trie.in", "r", stdin);
  freopen("trie.out", "w", stdout);
  int op;
  char cuv[LMAX + 5];
  nod *root = new nod;

  while(scanf("%d %s ", &op, cuv) != EOF) {
    if(op == 0)
      add_cuv(root, cuv, strlen(cuv));
    else if(op == 1)
      del_cuv(root, cuv, strlen(cuv));
    else if(op == 2)
      printf("%d\n", get_nr_ap(root, cuv, strlen(cuv)));
    else
      printf("%d\n", get_longest_prefix(root, cuv, strlen(cuv)));
  }

  return 0;
}