#include <iostream>
#include <string>
 
std::string without_brackets(std::string str, char beg = '(', char end = ')') {
	auto last = str.find_last_of(end);
	auto first = str.find_first_of(beg);
 
	if(last != std::string::npos) {
		str.erase(str.begin()+last);
	}
	if(first != std::string::npos) {
		str.erase(str.begin()+first);
	}
 
	return str;
}
 
 
using namespace std;
 
int main() {
	cout << without_brackets("abc)") << endl
	     << without_brackets("(abc") << endl
	     << without_brackets("(abc)") << endl
	     << without_brackets("abc") << endl;
	return 0;
}

I2luY2x1ZGUgPGlvc3RyZWFtPgojaW5jbHVkZSA8c3RyaW5nPgoKc3RkOjpzdHJpbmcgd2l0aG91dF9icmFja2V0cyhzdGQ6OnN0cmluZyBzdHIsIGNoYXIgYmVnID0gJygnLCBjaGFyIGVuZCA9ICcpJykgewoJYXV0byBsYXN0ID0gc3RyLmZpbmRfbGFzdF9vZihlbmQpOwoJYXV0byBmaXJzdCA9IHN0ci5maW5kX2ZpcnN0X29mKGJlZyk7CgkKCWlmKGxhc3QgIT0gc3RkOjpzdHJpbmc6Om5wb3MpIHsKCQlzdHIuZXJhc2Uoc3RyLmJlZ2luKCkrbGFzdCk7Cgl9CglpZihmaXJzdCAhPSBzdGQ6OnN0cmluZzo6bnBvcykgewoJCXN0ci5lcmFzZShzdHIuYmVnaW4oKStmaXJzdCk7Cgl9CgkKCXJldHVybiBzdHI7Cn0KCgp1c2luZyBuYW1lc3BhY2Ugc3RkOwoKaW50IG1haW4oKSB7Cgljb3V0IDw8IHdpdGhvdXRfYnJhY2tldHMoImFiYykiKSA8PCBlbmRsCgkgICAgIDw8IHdpdGhvdXRfYnJhY2tldHMoIihhYmMiKSA8PCBlbmRsCgkgICAgIDw8IHdpdGhvdXRfYnJhY2tldHMoIihhYmMpIikgPDwgZW5kbAoJICAgICA8PCB3aXRob3V0X2JyYWNrZXRzKCJhYmMiKSA8PCBlbmRsOwoJcmV0dXJuIDA7Cn0=