Submission #670812

#	Time	Username	Problem	Language	Result	Execution time	Memory
670812		mdub	Combo (IOI18_combo)	C++14	100 / 100	29 ms	588 KiB

combo

#include <bits/stdc++.h>

using namespace std;

int press(string p);

string guess_sequence(int N) {
  string first;
  string prefix, second;
  string th1, th2, th3;
  string other;
  if (press("AB")) {
    if (press("A"))
      first = "A";
    else
      first = "B";
  }
  else if (press("X")) {
    first = "X";
  }
  else first = "Y";
  
  if (first == "A") {
    prefix = "A";
    second = "B";
    th1 = "XB";
    th2= "XX";
    th3 = "XY";
    other = "Y";
  } 
  else if (first == "B") {
    prefix = "B";
    second = "A";
    th1 = "XA";
    th2 = "XX";
    th3 = "XY";
    other = "Y";
  }
  else if (first == "X") {
    prefix = "X";
    second = "A";
    th1 = "BB";
    th2 = "BA";
    th3 = "BY";
    other = "Y";
  }
  else {
    prefix = "Y";
    second = "A";
    th1 = "BB";
    th2 = "BX";
    th3 = "BA";
    other = "X"; 
  }
  if (N == 1) return prefix;
  for (int i = 1; i < N - 1; i++) {
    int temp = press(prefix + second + prefix + th1 + prefix + th2 + prefix + th3);
    if (temp == prefix.size()) prefix += other;
    else if (temp == prefix.size() + 1) prefix += second;
    else prefix += th1[0];
  }
  if (press(prefix+ second) == N) return prefix + second;
  else if (press(prefix + th1[0]) == N) return prefix + th1[0];
  else return prefix + other;
  
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:58:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   58 |     if (temp == prefix.size()) prefix += other;
      |         ~~~~~^~~~~~~~~~~~~~~~
combo.cpp:59:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   59 |     else if (temp == prefix.size() + 1) prefix += second;
      |              ~~~~~^~~~~~~~~~~~~~~~~~~~

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