#include <bits/stdc++.h>

using namespace std;
using ll = long long;
// #define int ll
using PII = pair<ll, ll>;

#define FOR(i, a, n) for (ll i = (ll)a; i < (ll)n; ++i)
#define REP(i, n) FOR(i, 0, n)
#define ALL(x) x.begin(), x.end()

template<typename T> T &chmin(T &a, const T &b) { return a = min(a, b); }
template<typename T> T &chmax(T &a, const T &b) { return a = max(a, b); }
template<typename T> bool IN(T a, T b, T x) { return a<=x&&x<b; }
template<typename T> T ceil(T a, T b) { return a/b + !!(a%b); }

template<typename T> vector<T> make_v(size_t a) { return vector<T>(a); }
template<typename T,typename... Ts>
auto make_v(size_t a,Ts... ts) {
    return vector<decltype(make_v<T>(ts...))>(a,make_v<T>(ts...));
}
template<typename T,typename V> typename enable_if<is_class<T>::value==0>::type
fill_v(T &t, const V &v) { t=v; }
template<typename T,typename V> typename enable_if<is_class<T>::value!=0>::type
fill_v(T &t, const V &v ) { for(auto &e:t) fill_v(e,v); }

template<class S,class T>
ostream &operator <<(ostream& out,const pair<S,T>& a) {
    out<<'('<<a.first<<','<<a.second<<')'; return out;
}
template<class T>
ostream &operator <<(ostream& out,const vector<T>& a){
    out<<'[';
    for(const T &i: a) out<<i<<',';
    out<<']';
    return out;
}
template<class T>
ostream &operator <<(ostream& out, const set<T>& a) {
    out<<'{';
    for(const T &i: a) out<<i<<',';
    out<<'}';
    return out;
}
template<class T, class S>
ostream &operator <<(ostream& out, const map<T,S>& a) {
    out<<'{';
    for(auto &i: a) out<<i<<',';
    out<<'}';
    return out;
}

int dx[] = {0, 1, 0, -1}, dy[] = {1, 0, -1, 0}; // DRUL
const int INF = 1<<30;
const ll LLINF = 1LL<<60;
const ll MOD = 1000000007;

string str;
ll pos;
ll expr() {
    ll ret;
    if(str[pos] == '-') {
        pos++;
        ret = !expr();
    } else if(str[pos] == '(') {
        pos++;
        ll vl = expr();
        char op = str[pos++];
        ll vr = expr();
        pos++;
        if(op == '*') ret = vl & vr;
        else ret = vl ^ vr;
    } else {
        ret = str[pos]-'0';
        pos++;
    }
    return ret;
}

ll func(string s) {
    ll ret = 0;
    REP(i, 1LL<<4) {
        string t = s;
        REP(j, t.size()) {
            if(t[j]=='a') t[j] = (i&1<<0) ? '0' : '1';
            if(t[j]=='b') t[j] = (i&1<<1) ? '0' : '1';
            if(t[j]=='c') t[j] = (i&1<<2) ? '0' : '1';
            if(t[j]=='d') t[j] = (i&1<<3) ? '0' : '1';
        }
        str = t, pos = 0;
        ret |= expr() << i;
    }
    return ret;
}

signed main(void)
{
    cin.tie(0);
    ios::sync_with_stdio(false);

    set<ll> st;
    vector<ll> ans(1LL<<16);
    vector<vector<string>> vs(17);
    FOR(i, 1, 17) {
        // 長さiの文字列を列挙
        vector<string> vv;
        if(i == 1) {
            vv.push_back("0");
            vv.push_back("1");
            vv.push_back("a");
            vv.push_back("b");
            vv.push_back("c");
            vv.push_back("d");
        }
        REP(j, vs[i-1].size()) vv.push_back("-"+vs[i-1][j]);
        FOR(j, 1, i-3) {
            ll k = i-3-j;
            if(k < 0) continue;
            REP(a, vs[j].size()) REP(b, vs[k].size()) {
                vv.push_back("(" + vs[j][a] + "^" + vs[k][b] + ")");
                vv.push_back("(" + vs[j][a] + "*" + vs[k][b] + ")");
            }
        }
        REP(j, vv.size()) {
            ll mask = func(vv[j]);
            if(st.find(mask) == st.end()) {
                ans[mask] = i;
                st.insert(mask);
                vs[i].push_back(vv[j]);
            }
        }
    }

    while(1) {
        string s;
        cin >> s;
        if(s == ".") break;
        cout << ans[func(s)] << endl;
    }

    return 0;
}



Measured memory_bytes: 4044