#include <bits/stdc++.h>
#define ll long long
#define ull unsigned long long
#define ld long double
#define chad char
#define mod 1'000'000'009
#define dim 100005
#define lim 1000000
#define INF 1000000000
#define FOR(i,a,b) for(int i=(a); i<=(b); i++)
#define piii pair<int,pair<int,int> > 
#define pii pair<int,int>
#define pll pair<ll,ll>
#define pb push_back
#define mp make_pair
#define nr_biti __builtin_popcount
using namespace std;
 
ifstream fin("trie.in");
ofstream fout("trie.out"); 

struct trie 
{
    struct nod 
    {
        int cnt;
        int nr;
        nod *next[26];

        nod()
        {
            nr=0;
            cnt=0;
            for(int i=0; i<26; i++)
                next[i]=nullptr;
        }
    };

    nod *rad=new nod;

    void insert(const string &a)
    {
        nod *aux=rad;

        for(int i=0; i<(int)a.size(); i++)
        {
            if(aux->next[a[i]-'a']==nullptr)
            {   
                aux->next[a[i]-'a']=new nod;
                aux=aux->next[a[i]-'a'];
                aux->cnt++;
            }
            else 
            {
                aux=aux->next[a[i]-'a'];
                aux->cnt++;
            }
        }

        aux->nr++;
    }

    int count(const string &a)
    {
        nod *aux=rad;

        for(int i=0; i<(int)a.size(); i++)
        {
            if(aux->next[a[i]-'a']==nullptr)
                return 0;
            else 
            {
                aux=aux->next[a[i]-'a'];
            }
        }

        return aux->nr;
    }

    int lcp(const string &a)
    {
        nod *aux=rad;
        int ans=0;

        for(int i=0; i<(int)a.size(); i++)
        {
            if(aux->next[a[i]-'a']==nullptr || aux->next[a[i]-'a']->cnt==0)
                return ans;
            else 
            {
                ans++;
                aux=aux->next[a[i]-'a'];
            }
        }

        return ans;
    }

    void erase(const string &a)
    {
        nod *aux=rad;

        for(int i=0; i<(int)a.size(); i++)
        {
            aux=aux->next[a[i]-'a'];
            aux->cnt--;
        }

        aux->nr--;
    }
}v;

int tip;
string s;

int main()
{
    ios_base::sync_with_stdio(false);
    fin.tie(nullptr);
    fout.tie(nullptr); 

    while(fin >> tip >> s)
    {
        if(tip==0)
        {
            v.insert(s);
        }
        else if(tip==1)
        {
            v.erase(s);
        }
        else if(tip==2)
        {
            fout << v.count(s) << "\n";
        }
        else 
        {
            fout << v.lcp(s) << "\n";
        }
    }
    
    return 0;
}