#include<fstream>
#include<string.h>
using namespace std;
ifstream f("trie.in");
ofstream g("trie.out");
int x;
char cuv[20];
class nod
{   public:
	int nr_cuvinte,pref_cuv;
	nod *fii[26],*tata;
}*rad=new nod;
void ad_cuv(char *w)
{   
	nod *aux=rad;
	for(int i=0;i<strlen(w);i++)
		if(aux->fii[w[i]-'a']==NULL)
		{  
			aux->fii[w[i]-'a']=new nod;
			aux->fii[w[i]-'a']->tata=aux;
			aux=aux->fii[w[i]-'a'];
			++aux->pref_cuv;
		}
        else
         {  
         	aux=aux->fii[w[i]-'a'];
         	++aux->pref_cuv;
		 }
   	++aux->nr_cuvinte;
}
void delete_cuv(char *w,int pas,struct nod *q)
{
	if(pas<=(strlen(w)-1))
	delete_cuv(w,pas+1,q->fii[w[pas]-'a']);
	if(pas==strlen(w)) --q->nr_cuvinte;
	--q->pref_cuv;
	if(q->pref_cuv==0&&q!=rad)
	{
		q->tata->fii[w[pas-1]-'a']=NULL;
		delete q;
	}

	
}
void print_nrcuv (char *w)
{
	nod *aux=rad; int i;
	for(i=0;i<strlen(w)&&aux->fii[w[i]-'a']!=NULL;i++)
	{
		aux=aux->fii[w[i]-'a'];
	}
	g<<(aux->nr_cuvinte)*(i==strlen(w))<<'\n';
}
void prefix_maxim(char *w)
{
	int i=0;
	nod *aux=rad;
	for(i=0;i<strlen(w)&&aux->fii[w[i]-'a']!=NULL;aux=aux->fii[w[i]-'a'],i++);
    g<<i<<'\n';
  
}
int main()
{
	while(f>>x>>cuv)
	{   
		switch(x)
		{
			case 0:
			ad_cuv(cuv);
			break;
			case 1:
			delete_cuv(cuv,0,rad);
			break;
			case 2:
			print_nrcuv(cuv);
			break;
			case 3:
			prefix_maxim(cuv);
			break;
		}
	}
	f.close();
	g.close();
  return 0;
}