#include <fstream>
#include <string>
#include <vector>
using namespace std;

ifstream cin ("trie.in");
ofstream cout ("trie.out");

struct TrieNode {
    int end_count=0;
    int prefix_count=0;
    TrieNode* children[26]={nullptr};
};

void insert(TrieNode* root, const string& w) {
    TrieNode* curr=root;
    for (char c:w) {
        int idx=c-'a';
        if (!curr->children[idx]) {
            curr->children[idx]=new TrieNode();
        }
        curr=curr->children[idx];
        curr->prefix_count++;
    }
    curr->end_count++;
}

void remove(TrieNode* root, const string& w) {
    TrieNode* curr=root;
    for (char c:w) {
        int idx=c-'a';
        TrieNode* next_node=curr->children[idx];
        next_node->prefix_count--;
        if (next_node->prefix_count==0) {
            curr->children[idx]=nullptr;
            curr=next_node;
            break;
        }
        curr=next_node;
    }
    curr->end_count--;
}

int count_word(TrieNode* root, const string& w) {
    TrieNode* curr=root;
    for (char c:w) {
        int idx=c-'a';
        if (!curr->children[idx] || curr->children[idx]->prefix_count==0) {
            return 0;
        }
        curr=curr->children[idx];
    }
    return curr->end_count;
}

int longest_prefix(TrieNode* root, const string& w) {
    TrieNode* curr=root;
    int length=0;
    for (char c:w) {
        int idx=c-'a';
        if (!curr->children[idx] || curr->children[idx]->prefix_count==0) {
            break;
        }
        curr=curr->children[idx];
        length++;
    }
    return length;
}

int main() {
    int op;
    string w;
    TrieNode* root=new TrieNode();
    while (cin>>op>>w) {
        if (op==0) {
            insert(root, w);
        } 
        else if (op==1) {
            remove(root, w);
        } 
        else if (op==2) {
            cout<<count_word(root, w)<<"\n";
        } 
        else if (op==3) {
            cout<<longest_prefix(root, w)<<"\n";
        }
    }
}