#include <iostream>
#include <cstdio>
#define CH (*s-'a')
#include <cstring>
using namespace std;

struct trie
{
    int nrcuv,nrfii;
    trie *fiu[28];
    trie()
    {
        nrcuv=nrfii=0;
        memset(fiu,0,sizeof(fiu));
    }
};

trie *t=new trie;

void ins(trie *nod,char *s)
{
    if(*s=='\n') { nod->nrcuv++; return;  }
    if(!nod->fiu[CH])
    {
        nod->fiu[CH]=new trie;
        nod->nrfii++;
    }
    ins(nod->fiu[CH],s+1);
}

int del(trie *nod, char *s)
{
    if(*s=='\n') nod->nrcuv--;
    else if( del( nod->fiu[CH],s+1))
         {
            nod->fiu[CH]=0;
            nod->nrfii--;
         }
    if(nod->nrfii==0 && nod->nrcuv==0 && nod!=t) { delete nod; return 1;}
    return 0;
}

int apar(trie *nod,char *s)
{
    if(*s=='\n') return nod->nrcuv;
    if(nod->fiu[CH]) return apar(nod->fiu[CH],s+1);
    else return 0;
}

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

int main()
{
    freopen("trie.in","r",stdin);
    freopen("trie.out","w",stdout);
    char line[25];
    fgets(line,25,stdin);

    while(!feof(stdin))
    {
        if(line[0]=='0') ins(t,line+2);
        if(line[0]=='1') del(t,line+2);
        if(line[0]=='2') printf("%d\n",apar(t,line+2));
        if(line[0]=='3') printf("%d\n",pref(t,line+2,0));
        fgets(line,25,stdin);
    }
    fclose(stdin);
    fclose(stdout);
    return 0;
}