Submission #616781

#	Time	Username	Problem	Language	Result	Execution time	Memory
616781		pirhosig	Combo (IOI18_combo)	C++17	100 / 100	37 ms	584 KiB

combo

#include "combo.h"
#include <bits/stdc++.h>
using namespace std;



string guess_sequence(int N) {
  char que[3];
  string ret = "";

  if (press("AB")) {
    que[0] = 'X';
    que[1] = 'Y';
    if (press("A")) {
      que[2] = 'B';
      ret = "A";
    }
    else {
      que[2] = 'A';
      ret = "B";
    }
  }
  else {
    que[0] = 'A';
    que[1] = 'B';
    if (press("X")) {
      que[2] = 'Y';
      ret = "X";
    }
    else {
      que[2] = 'X';
      ret = "Y";
    }
  }

  if (N == 1) return ret;

  // cerr << "S " << ret << " " << que[0] << " " << que[1] << " " << que[2] << endl;

  for (int i = 0; i < N - 2; ++i) {
    string query = ret + que[0] + que[0] + ret + que[0] + que[1] + ret + que[0] + que[2] + ret + que[1];
    // cerr << "T " << query << " " << query.size() << endl;
    int res = press(query);
    int s = (int)(ret.size());
    if (res == s) ret += que[2];
    else if (res == s + 1) ret += que[1];
    else ret += que[0];

    // cerr << "N " << ret << endl;
  }

  if (press(ret + que[0]) == N) ret += que[0];
  else if (press(ret + que[1]) == N) ret += que[1];
  else ret += que[2];

  // cerr << ret << endl;
  
  return ret;
}

• Subtask 1: 5 / 5
• Subtask 2: 95 / 95