#include <fstream>
#include <stack>
#include <string>
#include <cstring>
#define MAXN 100000
#define ll long long
std::ifstream input("evaluare.in");
std::ofstream output("evaluare.out");
std::stack<char> opstack;
ll position = 0, number, power = 1;
int priority(char c1, char c2)
{
	if (c1 == '+' && c2 == '-') return 1; if (c1 == '-' && c2 == '+') return 1;
	if (c1 == '*' && c2 == '/') return 1; if (c1 == '/' && c2 == '*') return 1;

	if (c1 == '+' && c2 == '*') return 1; if (c1 == '+' && c2 == '/') return 1;
	if (c1 == '-' && c2 == '*') return 1; if (c1 == '-' && c2 == '/') return 1;

	return 0;

}
ll operation(char operatorSymbol, ll x, ll y)
{
	switch (operatorSymbol)
	{
	case '+': return x + y;
	case '-': return y - x;
	case '/': return y / x;
	case '*': return x * y;
	}

	printf("error operation");
	return -1;
}
void infixTOpostfix(std::string& infixExpression, std::string& postfixExpression)
{
	long pos = 0, length = infixExpression.size();

	while (pos < length)
	{
		if (std::strchr("+-/*", infixExpression[pos]))
		{
			if (!opstack.size()) opstack.push(infixExpression[pos]);
			else if (priority(infixExpression[pos], opstack.top())) {
				postfixExpression = postfixExpression + opstack.top(); postfixExpression.append(" ");
				opstack.pop();
				opstack.push(infixExpression[pos]);
			}
			else opstack.push(infixExpression[pos]);
		}
		else if ('(' == infixExpression[pos]) opstack.push('(');
		else if (')' == infixExpression[pos])
		{
			//discarding ')'
			while (opstack.top() != '(') {
				postfixExpression = postfixExpression + opstack.top();
				postfixExpression.append(" ");
				opstack.pop();
			}
			opstack.pop();
		}
		else
		{
			while (pos < length && std::strchr("0123456789", infixExpression[pos]))
				postfixExpression += infixExpression[pos++];

			postfixExpression.append(" ");
			pos--;
		}
		pos++;
	}

	while (pos == length && opstack.size() != 0)
	{
		postfixExpression = postfixExpression + opstack.top();
		postfixExpression.append(" ");
		opstack.pop();
	}
}
ll evaluate(ll x, ll y, char op)
{
	switch (op)
	{
	case '+': return x + y;
	case '-': return x - y;
	case '/': return x / y;
	case '*': return x*y;
	}

	printf("something bad happened");
	return -1;
}
ll evaluatePostFix(std::string& expression)
{
	char op;
	if (strchr("+-/*", expression[position]))
	{
		op = expression[position];
		position -= 2;
		return evaluate(evaluatePostFix(expression), evaluatePostFix(expression), op);
	}


	number = 0; power = 1;
	while (position >= 0 && expression[position] != ' ')
	{
		number = number + (expression[position--] - '0') * power;
		power *= 10;
	}
	position--;
	return number;

	return -10;
}
int main()
{
	std::string infixExpression, postfixExpression;

	std::getline(input, infixExpression);

	infixTOpostfix(infixExpression, postfixExpression);

	position = postfixExpression.size() - 2;
	output << evaluatePostFix(postfixExpression);

	return 0;
}