#include <cstdio>
#include <cstring>

using namespace std;

struct Trie
{
 int cnt,nrfii;
 Trie *fiu[26];
 Trie()
 {
  cnt=nrfii=0;
  memset(fiu,0,sizeof(fiu));
 }
};

Trie *T=new Trie;

void ins(Trie *nod,char *s)
{
 if(*s=='\n')
 {
  nod->cnt++;
  return;
 }

 int ch =*s-'a';
 
 if(nod->fiu[ch]==0)
 {
  nod->fiu[ch]=new Trie;
  nod->nrfii ++;
 }

 ins(nod->fiu[ch],s+1);
}

int del(Trie *nod,char *s)
{
 if(*s=='\n')
  nod->cnt--;
 else
  if(del(nod->fiu[*s-'a'],s+1))
  {
   nod->fiu[*s-'a']=0;
   nod->nrfii--;
  }

  if(nod->cnt==0 && nod->nrfii==0 && nod != T )
  {
   delete nod;
   return 1;
  }
 return 0;
}

int que(Trie *nod,char *s)
{
 if(*s=='\n')
  return nod->cnt;
  
 if(nod->fiu[*s-'a'])
  return que( nod->fiu[ *s - 'a' ], s+1 );
  
 return 0;
}

int pre(Trie *nod,char *s,int k)
{
 if(*s=='\n' || nod->fiu[*s-'a']==0)
  return k;
 return pre(nod->fiu[*s-'a'],s+1,k+1);
}

int main()
{
 char line[32];

 freopen( "trie.in", "r", stdin );
 freopen( "trie.out", "w", stdout );

 fgets(line,32,stdin);

 while(!feof(stdin))
 {
  switch(line[0])
  {
   case '0': ins(T,line+2); break;
   case '1': del(T,line+2); break;
   case '2': printf("%d\n",que(T,line+2)); break;
   case '3': printf("%d\n",pre(T,line+2,0)); break;
  }

  fgets( line, 32, stdin );
 }
 return 0;
}