// Template v2
#define pb push_back
#define mp make_pair
#define first x
#define second y
#define l(x) x<<1
#define r(x) x<<1 | 1
#include<bits/stdc++.h>

using namespace std;

typedef long long LL;
typedef long double LD;
typedef vector<int> VI;
typedef pair<int, int> PII;
typedef pair<LL, LL> PLL;
typedef pair<double, double> PKK;
// primes less than 100
const int PRIM[] = {2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97};
const int CMAX = 350;
const int MOD = 1000000007;
const int NMAX = 1005;
const short INF16 = 32000;
const int INF = int(1e9);
const LL INF64 = LL(1e18);
const LD EPS = 1e-9, PI = acos(-1.0);

struct Trie{
	int a, b;
	Trie* next[26];
	Trie()
	{
		a=0; b=0;
		memset(next, 0, sizeof(next));
	}
};

Trie * R = new Trie;
string c;
int t;

void insert(Trie* node = R, int i=0)
{
	if(i==c.size())
	{
		node->b++;
		return;
	}
	if(node->next[c[i]-'a'] == NULL)
	{
		node->next[c[i]-'a']=new Trie;
		node->a++;
	}
	insert(node->next[c[i]-'a'], i+1);
}

bool pop(Trie* node = R, int i=0)
{
	if(i==c.size())
		node->b--;
	else
		if(pop(node->next[c[i]-'a'], i+1))
		{
			node->next[c[i]-'a']=NULL;
			node->a--;
		}

	if(node->b == 0 && node->a == 0 && node!=R)
	{
		delete node;
		return true;
	}
	return false;
}

int search(Trie* node = R, int i = 0)
{
	if(i==c.size())
		return node->b;
	if(node->next[c[i]-'a'])
		return search(node->next[c[i]-'a'], i+1);
	return 0;
}

int prefix(Trie* node = R, int i = 0)
{
	if(i==c.size())
		return i;
	if(node->next[c[i]-'a']==NULL)
		return i;
	return prefix(node->next[c[i]-'a'], i+1);
}

void read()
{
	while(cin>>t>>c)
	{
		if(t==0)
			insert();
		if(t==1)
			pop();
		if(t==2)
			cout<<search()<<"\n";
		if(t==3)
			cout<<prefix()<<"\n";
	}
}

int main() {
    cin.tie(0);
    ios_base::sync_with_stdio(0);
    cout << setprecision(16) << fixed;
    
    assert(freopen("trie.in", "rt", stdin));
    assert(freopen("trie.out", "wt", stdout));
    
    read();

    return 0;
}