Submission #109430

#	Time	Username	Problem	Language	Result	Execution time	Memory
109430		eu3neuom	Combo (IOI18_combo)	C++17	100 / 100	52 ms	552 KiB

combo

#include "combo.h"
#include <bits/stdc++.h>

using namespace std;

std::string guess_sequence(int N) {
    string S = "";
    int coins = press("AB");
    if (coins == 2) {
      S = "A";
    } else if (coins == 1) {
      if (press("A") == 1) {
        S = "A";
      } else {
        S = "B";
      }
    } else {
      if (press("X") == 1) {
        S = "X";
      } else {
        S = "Y";
      }
    }
    if (N == 1) return S;

    vector < char > pos = {'A', 'B', 'X', 'Y'};
    for (int i = 0; i < 4; ++i) {
      if (S[0] == pos[i]) {
        pos.erase(pos.begin() + i);
        break;
      }
    }

    for (int i = 1; i < N - 1; ++i) {
      string Q = S + pos[0] + S + pos[1] + pos[0] + S + pos[1] + pos[1] + S + pos[1] + pos[2];
      
      int coins = press(Q);
      if (coins == i) {
        S += pos[2];
      } else if (coins == (i + 1)) {
        S += pos[0];
      } else {
        S += pos[1];
      }
    }

    if (press(S + pos[0] + S + pos[1]) == N) {
      if (press(S + pos[0]) == N) {
        S += pos[0];
      } else {
        S += pos[1];
      }
    } else {
      S += pos[2];
    }
    return S;
}

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