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

using namespace std;

FILE *fin,*fout;

struct str
{
    int ap;
    int en;
    int fiu[27];
} a[120010];

int type;
char ch[21];
int p=2;
vector<int> dl;

void add()
{
    int ln=strlen(ch);
    int nod=1;

    for(int i=0;i<ln;i++)
    {
        if(a[nod].fiu[ch[i]-'a']==0)
        {
            if(dl.empty())
            {
                a[nod].fiu[ch[i]-'a']=p;
                p++;
            }
            else
            {
                a[nod].fiu[ch[i]-'a']=dl.back();
                dl.pop_back();
            }
        }
        a[a[nod].fiu[ch[i]-'a']].ap++;
        nod=a[nod].fiu[ch[i]-'a'];
    }
    a[nod].en++;
}

void del()
{
    int ln=strlen(ch);
    int nod=1;
    int nod1;

    for(int i=0;i<ln;i++)
    {
        a[a[nod].fiu[ch[i]-'a']].ap--;
        nod1=a[nod].fiu[ch[i]-'a'];
        if(a[a[nod].fiu[ch[i]-'a']].ap==0)
        {
            dl.push_back(a[nod].fiu[ch[i]-'a']);
            a[nod].fiu[ch[i]-'a']=0;
        }
        nod=nod1;
    }
    a[nod].en--;
}

void chk1()
{
    int ln=strlen(ch);
    int nod=1;

    for(int i=0;i<ln;i++)
    {
        if(a[nod].fiu[ch[i]-'a']!=0)
        {
            nod=a[nod].fiu[ch[i]-'a'];
        }
        else
        {
            fprintf(fout,"0\n");
            return;
        }
    }
    fprintf(fout,"%d\n",a[nod].en);
}

void chk2()
{
    int ln=strlen(ch);
    int nod=1;
    int ma=0;

    for(int i=0;i<ln;i++)
    {
        if(a[nod].fiu[ch[i]-'a']!=0)
        {
            nod=a[nod].fiu[ch[i]-'a'];
            ma++;
            if(a[nod].ap==0)
            {
                ma--;
                break;
            }
        }
        else
        {
            break;
        }
    }
    fprintf(fout,"%d\n",ma);
}

int main()
{
    fin=fopen("trie.in","r");
    fout=fopen("trie.out","w");

    while(!feof(fin))
    {
        fscanf(fin,"%d",&type);
        fscanf(fin,"%s",&ch);

        if(type==0)
        {
            add();
        }
        else if(type==1)
        {
            del();
        }
        else if(type==2)
        {
            chk1();
        }
        else
        {
            chk2();
        }
    }
}