#include <cmath>
#include <iostream>
#include <stack>
#include <unordered_map>
using namespace std;

unordered_map<char, int> priority{{'(', 0}, {')', 0}, {'+', 1}, {'-', 1},
                                  {'*', 2}, {'/', 2}, {'^', 3}};

string in_order2post_order(string src) {
  stack<char> in;
  string builder;
  for (int i = 0; i < src.size(); i++) {
    if (src[i] == ' ')
      continue;
    if (isdigit(src[i]))
      builder += src[i];
    else {
      builder += ' ';
      while (!in.empty() && priority[in.top()] >= priority[src[i]]) {
        builder += in.top();
        in.pop();
      }
      in.push(src[i]);
    }
  }
  if (builder[builder.size() - 1] != ' ')
    builder += ' ';
  while (!in.empty()) {
    builder += in.top();
    in.pop();
  }
  return builder;
}

int eval(string src) {
  stack<int> in;
  int num_builder = 0;
  for (int i = 0; i < src.size(); i++) {
    if (isdigit(src[i])) {
      num_builder = num_builder * 10 + src[i] - '0';
    } else if (src[i] == ' ') {
      in.push(num_builder);
      num_builder = 0;
    } else {
      int y = in.top();
      in.pop();
      int x = in.top();
      in.pop();
      switch (src[i]) {
      case '+':
        in.push(x + y);
        break;
      case '-':
        in.push(x - y);
        break;
      case '*':
        in.push(x * y);
        break;
      case '/':
        in.push(x / y);
        break;
      case '^':
        in.push(pow(x, y));
        break;
      }
    }
  }
  return in.top();
}

int main() {
  string str;
  getline(cin, str);
  cout << eval(in_order2post_order(str)) << endl;
}