Submission #1131499

#	Time	Username	Problem	Language	Result	Execution time	Memory
1131499		YouKnowCipher	Combo (IOI18_combo)	C++20	100 / 100	7 ms	484 KiB

combo

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

string guess_sequence (int N) {
	string s, t;
	if (press("AB")) {
		if (press("A")) s = "A";
		else s = "B";
	} else {
		if (press("X")) s = "X";
		else s = "Y"; 
	}
	if (N == 1) return s;
	if (s == "A") {
		t[0] = 'B', t[1] = 'X', t[2] = 'Y';
	}
	if (s == "B") {
		t[0] = 'A', t[1] = 'X', t[2] = 'Y';
	}
	if (s == "X") {
		t[0] = 'A', t[1] = 'B', t[2] = 'Y';
	}
	if (s == "Y") {
		t[0] = 'A', t[1] = 'B', t[2] = 'X';
	}
	for (int i = 1; i <= N - 2; i++) {
		string tmp = s + t[0] + t[0] + s + t[0] + t[1] + s + t[0] + t[2] + s + t[1];
		int cost = press(tmp);
		if (cost == i) s += t[2];
		else if (cost == i + 1) s += t[1];
		else s += t[0];
	}
	if (press(s + t[0]) == N) s += t[0];
	else if (press(s + t[1]) == N) s += t[1];
	else s += t[2];
	return s;
}

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