#include<cstdio>
#include<cstring>

using namespace std;

struct Node
{
    Node *F[30];
    int Nr,W;
    Node()
    {
        memset(F,0,sizeof(F));
        Nr = W = 0;
    }
} *Trie;

void Get_Query(char Line[],int &t,char Word[])
{
    t = Line[0] - '0';
    strcpy(Word,Line + 2);
    Word[strlen(Word) - 1]=0;
}

void Insert(char Word[])
{
    char *p;
    int c,l,i;
    Node *Q = Trie;
    Node *St[30];

    for(p = Word, l = 0; *p; p++)
    {
        c = *p - 'a';
        if(!Q->F[c]) Q->F[c] = new Node;
        Q = Q->F[c];
        St[++l] = Q;
    }
    Q->W++;
    for(i = 1; i <= l; i++)
        St[i]->Nr++;
}

void Delete(char Word[])
{
    char *p;
    int c,l,i;
    Node *Q = Trie;
    Node *St[30];

    for(p = Word, l = 0; *p; p++)
    {
        c = *p - 'a';
        Q = Q->F[c];
        Q->Nr--;
        St[++l] = Q;
    }
    Q->W--;
    p--;
    for(i = l; i >= 1; i--, p--)
        if(!St[i]->Nr)
        {
            c = *p - 'a';
            St[i-1]->F[c] = 0;
            delete St[i];
        }
        else break;
}

int Query(char Word[])
{
    char *p;
    int c;
    Node *Q = Trie;

    for(p = Word; *p; p++)
    {
        c = *p - 'a';
        if(!Q->F[c]) return 0;
        Q = Q->F[c];
    }

    return Q->W;
}

int Prefix_Lenght(char Word[])
{
    char *p;
    int c;
    Node *Q = Trie;

    for(p = Word; *p; p++)
    {
        c = *p - 'a';
        if(!Q->F[c]) break;
        Q = Q->F[c];
    }

    return p - Word;
}

int main()
{
    int t;
    char line[30],w[30];

    freopen("trie.in","r",stdin);
    freopen("trie.out","w",stdout);

    Trie = new Node;

    for(; fgets(line,30,stdin);)
    {
        Get_Query(line,t,w);

        if(t == 0) Insert(w);
        else if(t == 1) Delete(w);
        else if(t == 2) printf("%d\n",Query(w));
        else printf("%d\n",Prefix_Lenght(w));
    }

    return 0;
}