/*


*/

#include <fstream>
#include <vector>
#include <unordered_map>

class trie {
private:

    struct nodd {
        int cnt;
        std::unordered_map<char,nodd*> nxt;
        nodd() : cnt(0) {}
    }*root;

    bool erase(nodd *nod, const std::string &s, int idx) {
        if(idx==(int)s.size()) {
            if(nod->cnt>0) {
                nod->cnt--;
            }
            return nod->cnt==0 && nod->nxt.empty();
        }

        if(nod->nxt.find(s[idx])==nod->nxt.end())
            return 0;
        
        if(erase(nod->nxt[s[idx]],s,idx+1)) {
            delete nod->nxt[s[idx]];
            nod->nxt.erase(s[idx]);
        }
        return nod->cnt==0 && nod->nxt.empty();    
    }

    void clear(nodd *nod) {
        for(const auto &it:nod->nxt) {
            clear(it.second);
            delete it.second;
        }
    }

public:

    trie() {
        root=new nodd;
    }

    ~trie() {
        clear(root);
        delete root;
    }

    void insert(const std::string &s) {
        nodd *nod=root;
        for(int i=0; i<(int)s.size(); i++) {
            if(nod->nxt.find(s[i])==nod->nxt.end()) {
                nod->nxt[s[i]]=new nodd;
            }
            nod=nod->nxt[s[i]];
        }
        nod->cnt++;
    }

    int count(const std::string &s) {
        nodd *nod=root;
        for(int i=0; i<(int)s.size(); i++) {
            if(nod->nxt.find(s[i])!=nod->nxt.end()) {
                nod=nod->nxt[s[i]];
            }
            else {
                return 0;
            }
        }
        return nod->cnt;
    }

    int longest_prefix(const std::string &s) {
        nodd *nod=root;
        for(int i=0; i<(int)s.size(); i++) {
            if(nod->nxt.find(s[i])!=nod->nxt.end()) {
                nod=nod->nxt[s[i]];
            }
            else {
                return i;
            }
        }
        return (int)s.size();
    }

    void erase(const std::string &s) {
        erase(root,s,0);
    }
};

int main() {
    std::ifstream fin("trie.in");
    std::ofstream fout("trie.out");

    std::string s;
    int tip;
    trie v;

    while(fin >> tip >> s) {
        if(tip==0) {
            v.insert(s);
        }
        else if(tip==1) {
            v.erase(s);
        }
        else if(tip==2) {
            fout << v.count(s) << "\n";
        }
        else {
            fout << v.longest_prefix(s) << "\n";
        }
    }

    return 0;
}