#include <iostream>
#include <string>
#include <stack>
#include <unordered_map>
#include <vector>

using namespace std;

string s;
stack<char> op;
unordered_map<char, int> pr{{'+', 1}, {'-', 1}, {'*', 2}, {'/', 2}};//优先级
vector<string> r;//存储的是中转后的表达式比如 2 2 * 


int main() {
    cin >> s;

    //中转后缀
    for (int i = 0; i < s.size(); i ++) {

        if (isdigit(s[i])) {
            int j = i, x = 0;
            while (j < s.size() && isdigit(s[j])) x = x * 10 + (s[j ++] - '0');
            i = j - 1;
            r.push_back(to_string(x));//把对应的数字转换成字符串
        }
        else if (s[i] == '(') {
            op.push(s[i]);
        } 
        else if (s[i] == ')') 
        {
            while (op.top() != '(') {
                r.push_back(string{op.top()});//强制类型转换op.top()是char类型=>string
                op.pop();
            }
            op.pop();
        } 
        else 
        {
            while (op.size() && pr[op.top()] >= pr[s[i]]) //注意首先要判断栈是否存在
            {
                r.push_back(string{op.top()});
                op.pop();
            }
            op.push(s[i]);
        }
    }
    while (op.size()) {
        r.push_back(string{op.top()});
        op.pop();
    }

    stack<int> num;

    for (int i = 0; i < r.size(); i ++) {
        auto c = r[i];
        if (isdigit(c[0])) { // 这里c是一个字符串比如222，isdigit是判断一个字符，所以s[0];
            num.push(stoi(c));//字符转数字的强制转换
        } 
        else {
            auto b = num.top(); num.pop();
            auto a = num.top(); num.pop();
            int k = 0;
            if (c == "+") { // 注意这里c是字符串string类型的所以用"
                k = a + b;
            } else if (c == "-") {
                k = a - b;
            } else if (c == "*") {
                k = a * b;
            } else if (c == "/") {
                k = a / b;
            }
            nums.push(k);
        }
    }
    cout << nums.top() << endl;
    return 0;
}