#include <stdio.h>
#include <string.h>
#include <stdlib.h>


struct node 
{
	int freq,count;
	node * table[27];
};

node * root;
int c;
char * p;

void create(node ** x)
{  
     *x=(node *) malloc(sizeof(node));
	(*x)->freq=0;
	(*x)->count=0;
    memset((*x)->table,0,sizeof((*x)->table));
}

void add(node ** x,char * p)
{
   	if (*x==NULL)
   		 create(x);

   	(*x)->freq++;

   	if (*p==0)
   		(*x)->count++; else 
    add(&((*x)->table[*p-'a']),p+1);
}

void _delete(node ** x, char * p) 
{

	if (*p==0)
	{
      if ((*x)->freq==1)
      	 free(*x),*x=0; else 
      	 (*x)->freq--,(*x)->count--;
	}  
	   else 
	{

	   _delete(&(*x)->table[(*p-'a')],p+1);
		
	   if ((*x)->freq==1)
	   	free(*x),*x=0; else 
	    (*x)->freq--;
    }
}

int count(node * x, char * p)
{

	if (x==NULL)  return 0;

    if (*(p)==0)
    	return x->count; 

     return count(x->table[*p-'a'],p+1);
}

int pref(node * x,char * p,int k)
{
	//printf("%d %s-- \n",k,p);
	if (x==NULL)  return k-1;

	if (*(p)==0)
		return k;

	return pref(x->table[*p-'a'],p+1,k+1);
}


int main(int argc, char const *argv[])
{

	freopen("trie.in","r",stdin);
	freopen("trie.out","w",stdout);
	
     create(&root);
     p= (char *) malloc(25*sizeof(char));

   
     while (scanf("%d %s",&c,p)==2)
     {
       if (c==0)
       	add(&root->table[*p-'a'],p+1); else 
       if (c==1)
       	_delete(&root->table[*p-'a'],p+1); else 
       if (c==2)
       	 printf("%d\n",count(root->table[*p-'a'],p+1)); else 
       if (c==3)
       	printf("%d\n",pref(root->table[*p-'a'],p+1,1));
       memset(p,0,25);
     }


     fclose(stdin);
     fclose(stdout);

	return 0;
}