#include <bits/stdc++.h>
//#pragma GCC optimize("unroll-loops")

using namespace std;

typedef long long ll;
typedef pair<ll,ll> pll;
const int NMAX=755;
ifstream fin("trie.in");
ofstream fout("trie.out");
struct trie{
    struct node{
        int cnt=0,cnt2=0;
        node* children[26]{};
    }*root=new node;
    void insert(const string& s, int cnt=1){
        node* curr=root;
        root->cnt+=cnt;
        for(auto it : s){
            if(curr->children[it-'a']==NULL) curr->children[it-'a']=new node;
            curr=curr->children[it-'a'];
            curr->cnt+=cnt;
        }
        curr->cnt2+=cnt;
    }
    void erase(const string& s){
        insert(s,-1);
    }
    int count(const string& s){
        node* curr=root;
        for(auto it : s){
            if(curr->cnt==0 || curr->children[it-'a']==NULL) return 0;
            curr=curr->children[it-'a'];
        }
        return curr->cnt2;
    }
    int lcp(const string& s){
        node* curr=root;
        int depth=0;
        for(auto it : s){
            if(curr->children[it-'a']==NULL || curr->children[it-'a']->cnt==0) return depth;
            curr=curr->children[it-'a'],depth++;
        }
        return depth;
    }
}t;
int main()
{

    ios_base::sync_with_stdio(false); fout.tie(0);
    int type;
    string s;
    while(fin>>type>>s){
        switch(type){
            case 0: t.insert(s); break;
            case 1: t.erase(s); break;
            case 2: fout<<t.count(s)<<'\n'; break;
            case 3: fout<<t.lcp(s)<<'\n'; break;
        }
    }
    return 0;
}