#include <iostream>
#include <stack>
#include <string>

using namespace std;

int value(const string &expr)
{
    stack<int> vals;
    stack<char> ops;

    for (auto c : expr) {
        if (c == '(') {
            continue;
        } else if (c == 'm' || c == 'M') {
            ops.push(c);
        } else if (c == ')') {
            int a = vals.top(); vals.pop();
            int b = vals.top(); vals.pop();

            char op = ops.top(); ops.pop();

            vals.push(op == 'm' ? min(a, b) : max(a, b));
        } else {
            vals.push(c - '0');
        }
    }

    return vals.top();
}

int main(void)
{
    string expr;
    cin >> expr;

    cout << value(expr) << endl;

    return 0;
}