Merkkijono

input/code.cpp: In function 'int main()':
input/code.cpp:11:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i = 0; i < s.size(); i++) {
                              ^
input/code.cpp:19:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int b = i; b < s.size(); b++) {
                                ^

#include <iostream>
#include <string>
using namespace std;
string s;
bool ok;
char t;
int main() {
	cin >> s;
	while (1) {
		ok = true;
		for (int i = 0; i < s.size(); i++) {
			if (s.size() < 3) break;
			//cout << s.at(i) << ", " << s.at(i+1) << endl;
			if (s.at(i) == s.at(i+1)) {
				ok = false;
				//cout << s << endl;
				int alku = i;
				int loppu;
				for (int b = i; b < s.size(); b++) {
					if (s.at(b) != s.at(i)) {
						loppu = b - 1;
						break;
					}
				}
				//cout << alku << ", " << loppu << endl;
				s.erase(s.begin() + alku, s.begin() + loppu + 1);
				//cout << s << endl;
				break;
			}	
		}
		if (ok) break;
	}
	if (s.size() == 2 && s.at(0) == s.at(1)) s.clear();
	cout << s << endl;
}	
//DDDDJJJJGGGDDDDROOOE
//CAACCB

Test 1

Verdict: RUNTIME ERROR

terminate called after throwing an instance of 'std::out_of_range'
  what():  basic_string::at

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: RUNTIME ERROR

terminate called after throwing an instance of 'std::out_of_range'
  what():  basic_string::at

Test 5

Verdict: TIME LIMIT EXCEEDED

Test 6

Verdict: RUNTIME ERROR

terminate called after throwing an instance of 'std::out_of_range'
  what():  basic_string::at

Test 7

Verdict: RUNTIME ERROR

terminate called after throwing an instance of 'std::out_of_range'
  what():  basic_string::at

Test 8

Verdict: RUNTIME ERROR

terminate called after throwing an instance of 'std::out_of_range'
  what():  basic_string::at

Test 9

Verdict: RUNTIME ERROR

terminate called after throwing an instance of 'std::out_of_range'
  what():  basic_string::at

Test 10

Verdict: RUNTIME ERROR

terminate called after throwing an instance of 'std::out_of_range'
  what():  basic_string::at