Submission #829030

#	Time	Username	Problem	Language	Result	Execution time	Memory
829030		tranxuanbach	Combo (IOI18_combo)	C++17	100 / 100	65 ms	484 KiB

combo

#include "combo.h"

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

#define isz(a) ((signed)a.size())

string alphabet = "ABXY";

string guess_sequence(int n){
	string s = "";
	// first character
	if (press("AB") == 0){
		if (press("X") == 0){
			s += "Y";
		}
		else{
			s += "X";
		}
	}
	else{
		if (press("A") == 0){
			s += "B";
		}
		else{
			s += "A";
		}
	}
	alphabet.erase(alphabet.find(s), 1);
	for (int i = 1; i < n - 1; i++){
		string query = "";
		query += s + alphabet[0] + alphabet[0];
		query += s + alphabet[0] + alphabet[1];
		query += s + alphabet[0] + alphabet[2];
		query += s + alphabet[1];
		int val = press(query);
		if (val == isz(s) + 2){
			s += alphabet[0];
		}
		else if (val == isz(s) + 1){
			s += alphabet[1];
		}
		else{
			s += alphabet[2];
		}
	}
	if (n >= 2){
		string query = s + alphabet[0];
		int val1 = press(query);
		query = s + alphabet[1];
		int val2 = press(query);
		if (val1 == isz(s) + 1){
			s += alphabet[0];
		}
		else if (val2 == isz(s) + 1){
			s += alphabet[1];
		}
		else{
			s += alphabet[2];
		}
	}
	return s;
}

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