Submission #1290203

#	Time	Username	Problem	Language	Result	Execution time	Memory
1290203		Alphanumeric	Combo (IOI18_combo)	C++20	Compilation error	0 ms	0 KiB

combo

string guess_sequence(int n) {
  string chars = "ABXY";
  int res;
  string s;
  for0(3) {
    string it;
    it.push_back(chars[i]);
    res = press(it);
    if (res) s = it;
  }
  if (s.size() == 0) s = "Y";
  string ch;
  for0(4) {
    string it;
    it.push_back(chars[i]);
    if (it != s) ch.push_back(chars[i]);
  }
  string a, b, c;
  a.push_back(ch[0]);
  b.push_back(ch[1]);
  c.push_back(ch[2]);
  for0(n - 1) {
    res = press(s + a + s + b + a + s + b + b + s + b + c);
    if (res == 0) s += c;
    if (res == 1) s += a;
    if (res == 2) s += b;
  }
  return s;
}

Compilation message (stderr)

combo.cpp:1:1: error: 'string' does not name a type
    1 | string guess_sequence(int n) {
      | ^~~~~~