Submission #1007470

#	Time	Username	Problem	Language	Result	Execution time	Memory
1007470		kebine	Combo (IOI18_combo)	C++17	100 / 100	20 ms	1864 KiB

combo

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

/*

c = "abxy"

n = 8
abbxyxxb

y = n
x = n
b = n
udah pasti a

abax

*/

string guess_sequence(int n) {

  // guess 1st char of s
  // sisa question: n + 2 - 2 = n
  string s;
  int val = press("AB");
  
  if (val == 2) {
    s = "A";
  } else if (val == 1) {
    
    if (press("A") == 1) {
      s = "A";
    } else {
      s = "B";
    }
    
  } else {
    
    if (press("X") == 1) {
      s = "X";
    } else {
      s = "Y";
    }
    
  }
  if (n == 1) {
    return s;
  }

  // length sisa (n - 1), questions sisa n
  vector<string> ch;
  if (s[0] != 'A') {
    ch.push_back("A");
  }
  if (s[0] != 'B') {
    ch.push_back("B");
  }
  if (s[0] != 'X') {
    ch.push_back("X");
  }
  if (s[0] != 'Y') {
    ch.push_back("Y");
  }

  for (int i = 2; i <= n - 1; ++i) {

    val = press(s + ch[0] + s + ch[1] + ch[0] + s + ch[1] + ch[1] + s + ch[1] + ch[2]);

    if (val == i - 1) {
      s += ch[2];
    } else if (val == i) {
      s += ch[0];
    } else { // val == i + 1
      s += ch[1];
    }
  }

  if (press(s + ch[0]) == n) {
    s += ch[0];
  } else if (press(s + ch[1]) == n) {
    s += ch[1];
  } else {
    s += ch[2];
  }
  
  return s;
}

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