Submission #554893

#	Time	Username	Problem	Language	Result	Execution time	Memory
554893		d4xn	Combo (IOI18_combo)	C++17	5 / 100	1 ms	272 KiB

combo

#include "combo.h"

#pragma GCC optimize ("Ofast")
#include <bits/stdc++.h>
using namespace std;

#define pb push_back

string guess_sequence(int N) {
  string p;

  string dict1 = "ABXY";

  int x = press("AB");
  if (x >= 1) {
    if (press("A")) {
      p.pb('A');
    }
    else {
      p.pb('B');
    }
  }
  else {
    if (press("X")) {
      p.pb('X');
    }
    else {
      p.pb('Y');
    }
  }

  string dict2;
  for (char &c : dict1) {
    if (c == p[0]) continue;
    dict2.pb(c);
  }

  x = 1;
  for (int i = 1; i < N-1; i++) {
    string s1 = p;
    s1.pb(dict2[0]);

    string s2 = p;
    s2.pb(dict2[1]);
    s2.pb(dict2[0]);

    string s3 = p;
    s3.pb(dict2[1]);
    s3.pb(dict2[1]);

    string s4 = p;
    s4.pb(dict2[1]);
    s4.pb(dict2[2]);

    int y = press(s1 + s2 + s3 + s4);
    if (y == x+1) {
      p.pb(dict2[0]);
    }
    else if (y == x+2) {
      p.pb(dict2[1]);
    }
    else {
      p.pb(dict2[2]);
    }

    x++;
  }

  for (int i = 0; i < 2; i++) {
    char c = dict2[i];
    p.pb(c);
    if (press(p) == N) break;
    p.pop_back();
  }
  
  if (p.size() < N) {
    p.pb(dict2[2]);
  }

  return p;
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:76:16: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   76 |   if (p.size() < N) {
      |       ~~~~~~~~~^~~

• Subtask 1: 5 / 5
• Subtask 2: 0 / 95