#include <stdio.h>
#include <cmath>
#include <algorithm>
#include <cfloat>
#include <stack>
#include <queue>
#include <vector>
#include <string>
#include <iostream>
#include <set>
#include <map>
#include <time.h>
typedef long long int ll;
typedef unsigned long long int ull;
#define BIG_NUM 2000000000
#define MOD 1000000007
#define EPS 0.000000001
using namespace std;


int POW[17];
int min_length[65536];
char num[2] = {'0','1'},var[4] = {'a','b','c','d'},alloc_table[16][4];

struct Info{
	string tmp_str;
	int index;
};


int makeCode(int array[16]){

	int ret = 0;

	for(int i = 0; i < 16; i++){
		ret += array[i]*POW[i];
	}

	return ret;
}

int calc_two(char op,int a,int b){

	if(op == '^'){

		return abs(a-b);

	}else{ //op == '*'
		return a*b;
	}
}


int calc_equation(char buf[17],int left,int right){

	int depth = 0,loc,max_depth = 0;
	char op = '@';

	for(int i = left; i <= right; i++){
		if(buf[i] == '('){
			depth++;
			max_depth = max(max_depth,depth);
		}else if(buf[i] == ')'){
			depth--;
		}else if(buf[i] == '^' || buf[i] == '*'){
			if(depth == 0){
				op = buf[i];
				loc = i;
				break;
			}
		}
	}

	if(op == '@'){

		if(max_depth > 0){

			if(buf[left] == '-'){ //-<E>

				int minus_num = 0,loc = left;
				while(buf[loc] == '-'){
					minus_num++;
					loc++;
				}

				if(buf[loc] == '('){
					if(minus_num%2 == 0){
						return calc_equation(buf,loc,right);
					}else{
						return 1-calc_equation(buf,left+1,right);
					}
				}else{

					if(minus_num%2 == 0){
						return buf[loc]-'0';
					}else{
						return 1-(buf[loc]-'0');
					}
				}
			}else{
				return calc_equation(buf,left+1,right-1);
			}

		}else{

			int not_num = 0,tmp_index = left;

			while(buf[tmp_index] == '-'){
				not_num++;
				tmp_index++;
			}

			if(not_num%2 == 0){
				return buf[tmp_index]-'0';
			}else{

				return 1-(buf[tmp_index]-'0');
			}
		}

	}else{

		int left_num = calc_equation(buf,left,loc-1);
		int right_num = calc_equation(buf,loc+1,right);

		return calc_two(op,left_num,right_num);
	}
}


int calc_all_pattern(char buf[17]){

	int result[16];
	char tmp_buf[17];

	int length;
	for(length = 0; buf[length] != '\0'; length++);

	for(int i = 0; i < 16; i++){

		for(int k = 0; k < length; k++){
			if(buf[k] >= 'a' && buf[k] <= 'd'){
				tmp_buf[k] = alloc_table[i][buf[k]-'a'];
			}else{
				tmp_buf[k] = buf[k];
			}
		}
		tmp_buf[length] = '\0';

		result[i] = calc_equation(tmp_buf,0,length-1);
	}

	return makeCode(result);
}


void makeEquation(){

	vector<string> S;
	S.push_back("a");
	S.push_back("-a");
	S.push_back("b");
	S.push_back("-b");
	S.push_back("c");
	S.push_back("-c");
	S.push_back("d");
	S.push_back("-d");

	vector<string> WORK;

	for(int depth = 0; depth < 3; depth++){
		WORK.clear();
		for(int i = 0; i < S.size(); i++){
			for(int k = i; k < S.size(); k++){
				if(S[i].size()+S[k].size()+3 > 16)continue;

				string eq_1 = "(" + S[i] + "*" + S[k] + ")";
				string eq_2 = "(" + S[i] + "^" + S[k] + ")";

				WORK.push_back(eq_1);
				WORK.push_back(eq_2);

				if(eq_1.size()+1 <= 16){
					WORK.push_back("-" + eq_1);
				}
				if(eq_2.size()+1 <= 16){
					WORK.push_back("-" + eq_2);
				}
			}
		}
		for(int k = 0; k < WORK.size(); k++){
			S.push_back(WORK[k]);
		}
	}

	S.push_back("0");
	S.push_back("1");

	int tmp_code;
	char buf[17];

	for(int i = 0; i < S.size(); i++){

		for(int k = 0; k < S[i].size(); k++){
			buf[k] = S[i][k];
		}
		buf[S[i].size()] = '\0';

		tmp_code = calc_all_pattern(buf);

		min_length[tmp_code] = min(min_length[tmp_code],(int)S[i].size());
	}
}

void makeTable(){

	int index = 0;

	for(int a = 0; a < 2; a++){
		for(int b = 0; b < 2; b++){
			for(int c = 0; c < 2; c++){
				for(int d = 0; d < 2; d++){
					alloc_table[index][0] = '0'+a;
					alloc_table[index][1] = '0'+b;
					alloc_table[index][2] = '0'+c;
					alloc_table[index][3] = '0'+d;
					index++;
				}
			}
		}
	}
}


int main(){

	for(int i = 0; i < 17; i++)POW[i] = pow(2,i);

	for(int i = 0; i < POW[16]; i++)min_length[i] = BIG_NUM;

	makeTable();
	makeEquation();

	char buf[17];

	while(true){
		scanf("%s",buf);
		if(buf[0] == '.')break;

		printf("%d\n",min_length[calc_all_pattern(buf)]);
	}

	return 0;
}



Measured memory_bytes: 26628