# pragma GCC optimize("O3")
# include <bits/stdc++.h>
# define maxn 100005
# define ll long long
# define clock (clock() * 1000.0 / CLOCKS_PER_SEC)
# define rc(s) return cout << s,0
# define _ ios_base::sync_with_stdio(false);cin.tie(0);cerr.tie(0);cout.tie(0);
# define db(x) cerr << #x << " = " << x << '\n'
# define pb push_back
# define mp make_pair
# define sz(x) (int)((x).size())
//# define int ll
using namespace std;
  
int t[1 << 21];
int op;
string s;
map<int,int>nxt[27];
int idx;
  
void add(string s)
{
    int curr = 0;
    s += '{';
    for(auto it : s)
    {
        if(!nxt[it - 'a'][curr]) nxt[it - 'a'][curr] = ++idx;
        curr = nxt[it - 'a'][curr];
        t[curr]++;
    }
}
  
void del(string s)
{
    int curr = 0;
    s += '{';
    for(auto it : s)
    {
        curr = nxt[it - 'a'][curr];
        t[curr]--;
    }
}
  
int cnt(string s)
{
    int curr = 0;
    s += '{';
    for(auto it : s)
    {
        curr = nxt[it - 'a'][curr];
        if(!curr || !t[curr]) return 0;
    }
    return t[curr];
}
  
int mxprf(string s)
{
    int curr = 0;
    int ans = 0;
    for(auto it : s)
    {
        curr = nxt[it - 'a'][curr];
        if(!curr || !t[curr]) return ans;
        ans++;
    }
    return ans;
}
  
int32_t main(){_
    //freopen("input","r",stdin);
    freopen("trie.in","r",stdin);
    freopen("trie.out","w",stdout);
    while(cin >> op >> s)
    {
        if(op == 0) add(s);
        else if(op == 1) del(s);
        else if(op == 2) cout << cnt(s) << '\n';
        else cout << mxprf(s) << '\n';
    }
}