Submission #766878

#	Time	Username	Problem	Language	Result	Execution time	Memory
766878		oyber	Combo (IOI18_combo)	C++14	100 / 100	24 ms	692 KiB

combo

#include "combo.h"
#include <vector>
#include <iostream>
using namespace std;

string guess_sequence(int N) {
  vector<char> letters = {'A', 'B', 'X', 'Y'};
  string start1 = "AB";
  int score = press(start1);
  string p = "";
  if (score > 0) {
    string start2 = "B";
    int score = press(start2);
    if (score > 0) {
      letters.erase(letters.begin() + 1);
      p += "B";
    } else {
      letters.erase(letters.begin());
      p += "A";
    }
  } else {
    string start2 = "X";
    int score = press(start2);
    if (score > 0) {
      letters.erase(letters.begin() + 2);
      p += "X";
    } else {
      letters.erase(letters.begin() + 3);
      p += "Y";
    }
  }

  if (N == 1) {
    return p;
  }

  for (int i = 1; i < N-1; i++) {
    string p1 = p + letters[0] + p + letters[1] + letters[0] + p + letters[1] + letters[1] + p + letters[1] + letters[2];
    int score = press(p1);
    if (score == i) {
      p += letters[2];
    } else if (score == i+1) { 
      p += letters[0];
    } else if (score == i+2) {
      p += letters[1];
    }
  }

  string end1 = p + letters[0];
  score = press(end1);
  if (score == N) {
    return end1;
  }
  string end2 = p + letters[1];
  score = press(end2);
  if (score == N) {
    return end2;
  }

  return p + letters[2];
}

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