/* Propositional logic translator, infix-to-postfix
   Sten Morten Andersen, 2003 
   
Grammar:

formula    ::= expression { ('>' | '=') formula }
expression ::= term { 'v' term }
term       ::= factor { '&' factor }
factor     ::= 'a' | 'b' | 'c' | .. | 'z' | 
               '-' formula |
               '(' formula ')'
*/
char ch;
char stack[100]; int top;
void formula();

void error(char *s) { printf("%s. Seen %c\n", s, ch); exit(1); }

void get_char() {
	do ch = getchar(); while ( ch <= ' ' );
}

void factor() {
	char c = ch;
	if ( ch == '0' || ch == '1' ) ch = 'L';
	switch( ch ) {
		case 'L': stack[ top++ ] = c; get_char(); break;
		case '-':
			get_char();
			formula();
			stack[ top++ ] = 'N';
		break;
		case '(':
			get_char();
			formula();
			if ( ch != ')' ) error("Missing )");
			get_char();
		break;
		default:
			error("Expected 0, 1 or (formula)");
	}	 
}

void term() {
	factor();
	while ( ch == '&' ) {
		get_char();
		factor();
		stack[ top++ ] = 'K';
	} 
}

void expression() {
	term();
	while ( ch == 'v' ) {
		get_char();
		term();
		stack[ top++ ] = 'A';
	} 
}

void formula() {
	char c;
	expression();
	while ( ch == '>' || ch == '=') {
		c = ch;
		get_char();
		formula();
		if ( c == '=' ) stack[ top++ ] = 'E';
		if ( c == '>' ) stack[ top++ ] = 'C';
	} 
}

int eval() {
	int i, t = -1;
	int s[100];
	
	for ( i = 0; i < top; i++ ) {
		if ( stack[ i ] == '0' || stack[ i ] == '1' ) {
			t++;
			s[ t ] = stack[ i ]-'0';
		} else {
			t--;
			switch ( stack[ i ] ) {
				case 'A': s[ t ] = s[ t ] || s[ t+1 ]; break;
				case 'C': s[ t ] = s[ t ] <= s[ t+1 ]; break;
				case 'E': s[ t ] = s[ t ] == s[ t+1 ]; break;
				case 'K': s[ t ] = s[ t ] && s[ t+1 ]; break;
				case 'N': t++; s[ t ] = ! s[ t ];      break;
			}
		}
	}
	return s[ t ]; 
}

int main() {
	top = 0;
	get_char();
	formula();
	if ( ch != '.') error ("Expected .");
	int e = eval();
	printf("%d",e);
	return 0;
}