Submission #1110890

#	Time	Username	Problem	Language	Result	Execution time	Memory
1110890		HasanV11010238	Combo (IOI18_combo)	C++17	100 / 100	50 ms	2108 KiB

combo

#include "combo.h"
#include <vector>
using namespace std;
vector<char> c = {'A', 'B', 'X', 'Y'};
string guess_sequence(int N){
  string ans = "", q;
  int l = 0, r = 3;
  while (l != r){
    int mid = (l + r) / 2;
    q = "";
    for (int i = l; i <= mid; i++){
      q += c[i];
    }
    if (press(q) == 0){
      l = mid + 1;
    }
    else{
      r = mid;
    }
  }
  vector<char> al;
  for (int i = 0; i < 4; i++){
    if (l != i){
      al.push_back(c[i]);
    }
  }
  ans += c[l];
  if (N == 1) return ans;
  for (int i = 0; i < N - 2; i++){
    q = ans + al[0] + ans + al[1] + al[0] + ans + al[1] + al[1] + ans + al[1] + al[2];
    int res = press(q);
    if (res == i + 1){
      ans += al[2];
    }
    else if (res == i + 2){
      ans += al[0];
    }
    else{
      ans += al[1];
    }
  }
  
  if (press(ans + al[0]) == N) return ans + al[0];
  if (press(ans + al[1]) == N) return ans + al[1];
  return ans + al[2];
}

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