#include <cstdio>

using namespace std;

struct trie
{
    int finish = 0, counter = 0;
    struct trie *next[27] = {0};
};

trie *root = new trie;

void add(trie *& nod, char *s)
{
    if(*s == 0)
    {
        nod -> finish++;
        return;
    }
    if(nod -> next[*s - 'a'] == 0)
    {
        nod -> next[*s - 'a'] = new trie;
        nod -> counter++;
    }
    add(nod -> next[*s - 'a'], s + 1);
}
int del(trie *& nod, char *s)
{
    if(*s == 0)
        nod -> finish--;
    else
        if(del(nod -> next[*s-'a'], s + 1))
        {
            nod -> counter--;
            nod -> next[*s - 'a'] = 0;
        }
    if(nod -> counter == 0 && nod -> finish == 0 && nod != root)
    {
        delete nod;
        return 1;
    }
    return 0;
}
int apcuv(trie *nod, char *s)
{
    if(*s == 0)
        return nod -> finish;
    if(nod -> next[*s - 'a'])
        return apcuv(nod -> next[*s - 'a'], s + 1);
    return 0;
}
int prefix(trie *nod, char *s, int k)
{
    if(*s == 0 || nod -> next[*s - 'a'] == 0)
        return k;
    return prefix(nod -> next[*s - 'a'], s + 1, k + 1);
}
int main()
{
	freopen("trie.in", "r", stdin);
	freopen("trie.out", "w", stdout);
	int operatie;
	char a[24];
    while(scanf("%d %s\n", &operatie, a) == 2)
    {
        switch(operatie)
        {
        	case 0: add(root,a); break;
        	case 1:	del(root,a); break;
        	case 2:	printf("%d\n", apcuv(root,a)); break;
        	case 3: printf("%d\n", prefix(root,a,0));
        }

	}
    return 0;
}