Submission #1006785

#	Time	Username	Problem	Language	Result	Execution time	Memory
1006785		kebine	Combo (IOI18_combo)	C++17	100 / 100	22 ms	1760 KiB

combo

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

string guess_sequence(int N) {
  string S = "";
  char a;
  string p = "AB";
  int coins = press(p);
  if(coins){
    p = "A";
    coins = press(p);
    if(coins) a = 'A';
    else a = 'B';
  }
  else{
    p = "X";
    coins = press(p);
    if(coins) a = 'X';
    else a = 'Y';
  }
  S += a;
  if(N == 1) return S;
  vector <char> v;
  if(a != 'A') v.push_back('A');
  if(a != 'B') v.push_back('B');
  if(a != 'X') v.push_back('X');
  if(a != 'Y') v.push_back('Y');

  for(int i = 2; i <= N-1; i++){
    p = "";
    for(auto x : v) p += S + v[0] + x;
    p += S + v[1];
    coins = press(p);

    if(coins == i+1) S += v[0];
    else if(coins == i) S += v[1];
    else S += v[2];
  }
  p = S + v[0] + S + v[1];
  coins = press(p);
  if(coins == N){
    p = S + v[0];
    coins = press(p);
    if(coins == N) S += v[0];
    else S += v[1];
  }
  else S += v[2];
  return S;
}

// int main(){
//   ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
// }

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