Submission #418135

#	Time	Username	Problem	Language	Result	Execution time	Memory
418135		ja_kingy	Combo (IOI18_combo)	C++14	100 / 100	31 ms	688 KiB

combo

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

std::string guess_sequence(int N) {
  string ls = "ABXY";
  string ans;
  if (N == 1) {
    if (press("A")) return "A";
    else if (press("B")) return "B";
    else if (press("X")) return "X";
    else return "Y";
  }
  if (press("AB")) {
    ans = press("A") ? "A" : "B";
  } else {
    ans = press("X") ? "X" : "Y";
  }
  ls.erase(find(ls.begin(), ls.end(), ans[0]));
  string p;
  for (int i = 1; i < N-1; ++i) {
    p = ans + ls[0] + ls[0] + ans + ls[0] + ls[1] + ans + ls[0] + ls[2] + ans + ls[1];
    int res = press(p);
    if (res == ans.size() + 2) {
      ans.push_back(ls[0]);
    } else if(res == ans.size()+1) {
      ans.push_back(ls[1]);
    } else {
      ans.push_back(ls[2]);
    }
  }
  p = ans + ls[0];
  if (press(p) == N) ans.push_back(ls[0]);
  else {
    p = ans + ls[1];
    if (press(p) == N) ans.push_back(ls[1]);
    else {
      ans.push_back(ls[2]);
    }
  }
  return ans;
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:24:13: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |     if (res == ans.size() + 2) {
      |         ~~~~^~~~~~~~~~~~~~~~~
combo.cpp:26:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   26 |     } else if(res == ans.size()+1) {
      |               ~~~~^~~~~~~~~~~~~~~

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