Submission #630472

#	Time	Username	Problem	Language	Result	Execution time	Memory
630472		NintsiChkhaidze	Combo (IOI18_combo)	C++14	100 / 100	32 ms	576 KiB

combo

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

vector<char> v = {'A', 'B', 'X', 'Y'}, w;
string guess_sequence(int N) {
  string S = "";
  char f = v[3];
  
  string k = "AB";
  if (press(k)){
    f = 'B';
    if (press("A")) f = 'A';
  }else{
    f = 'Y';
    if (press("X")) f = 'X';
  }

  S += f;
  for (auto c : v)
    if (c != f)
      w.pb(c);

  while (S.size() < N - 1) {
    string p = S + w[0] + S + w[1] + w[0] + S + w[1] + w[1] + S + w[1] + w[2];
    int coins = press(p), s = S.size();
    if (coins == s)
      S += w[2];
    else if (coins == s + 1)
      S += w[0];
    else if (coins == s + 2)
      S += w[1];
  }

  if (N > 1) {
    char ls = w[2];
    for (int i = 0; i < 2; i++) {
      string P = S + w[i];
      if (press(P) == S.size() + 1) {
        ls = w[i];
        break;
      }
    }

    S += ls;
  }
  
  return S;
}

// ABXYBXXXXBY

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:25:19: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   25 |   while (S.size() < N - 1) {
      |          ~~~~~~~~~^~~~~~~
combo.cpp:40:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   40 |       if (press(P) == S.size() + 1) {
      |           ~~~~~~~~~^~~~~~~~~~~~~~~

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