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

using namespace std;

bool solutioneke(string s)
{
    bool answer = true;
    stack<char> arr;
    for (char i : s) {
        if (i == '(') {
            arr.push(i);
        }
        else {
            if (arr.empty()) {
                answer = false;
                return answer;
            }
            arr.pop();
        }
        
    }
    if (!arr.empty())
        answer = false;

    return answer;
}

int main() {
    string s;
    cin >> s;

    if (solutioneke(s))
        cout << "true" << endl;
    else
        cout << "false" << endl;

    return 0;
}