Submission #880926

#	Time	Username	Problem	Language	Result	Execution time	Memory
880926		theghostking	Combo (IOI18_combo)	C++17	100 / 100	14 ms	2040 KiB

combo

#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
std::string guess_sequence(int N) {
  std::string p = "";
  std::vector<char> vec = {'A','B','X','Y'};
  char st;
  int coin = press("AB");
  if (coin == 1){
    coin = press("A");
    if (coin == 1){
      st = 'A';
    }
    else{
      st = 'B';
    }
  }
  else if (coin != 2){
    coin = press("X");
    if (coin == 1){
      st = 'X';
    }
    else{
      st = 'Y';
    }
  }
  if (coin == 2){
      st = 'A';
  }
  auto it = find(vec.begin(),vec.end(),st);
  vec.erase(it);
  p.push_back(st);
  if (coin == 2){
      p.push_back('B');
  }
  for (int i = p.size(); i<N-1; i++){
    string guess;
    string one = p; one.push_back(vec[0]); one.push_back(vec[0]);
    string two = p; two.push_back(vec[0]); two.push_back(vec[1]);
    string three = p; three.push_back(vec[0]); three.push_back(vec[2]);
    string four = p; four.push_back(vec[1]);
    guess = one + two + three + four;
    int res = press(guess);
    char nxt;
    if (res == i){
      nxt = vec[2];
    }
    else if (res == i+1){
      nxt = vec[1];
    }
    else{
      nxt = vec[0];
    }
    p.push_back(nxt);
  }
  int sz = p.size();
  if (sz == N){
    return p;
  }
  char lst;
  string guess;
  string ek = p; ek.push_back(vec[0]);
  string doo = p; doo.push_back(vec[1]);
  guess = ek+doo;
  int c = press(guess);
  if (c == sz){
    lst = vec[2];
  }
  else{
    guess = p; guess.push_back(vec[0]);
    c = press(guess);
    if (c == sz){
      lst = vec[1];
    }
    else{
      lst = vec[0];
    }
  }
  p.push_back(lst);
  return p;
}

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