Submission #862333

#	Time	Username	Problem	Language	Result	Execution time	Memory
862333		aykhn	Combo (IOI18_combo)	C++14	100 / 100	13 ms	1960 KiB

combo

#include "combo.h"
#include <bits/stdc++.h>
 
// author : aykhn
 
using namespace std;
typedef long long ll;
 
#define pb push_back
#define ins insert
#define mpr make_pair
#define all(v) v.begin(), v.end()
#define bpc __builtin_popcount
#define bpcll __builtin_popcountll
#define pii pair<int, int>
#define pll pair<ll, ll>
#define fi first
#define se second
#define infll 0x3F3F3F3F3F3F3F3F
#define inf 0x3F3F3F3F
 
string guess_sequence(int N) 
{
	string res = "";
	int x = press("AB");
	if (x)
	{
		x = press("A");
		if (x) res = "A";
		else res = "B";
	}
	else
	{
		x = press("X");
		if (x) res = "X";
		else res = "Y";
	}
	if (N == 1) return res;
	string temp = "ABXY";
	string ch;
	for (int i = 0; i < 4; i++) if (temp[i] != res[0]) ch.pb(temp[i]);
	int prev = 1;
	int cnt = 2;
	for (int i = 1; i + 1 < N; i++)
	{
		string s = res;
		s.pb(ch[0]);
		s += res;
		s.pb(ch[1]);
		s.pb(ch[0]);
		s += res;
		s.pb(ch[1]);
		s.pb(ch[1]);
		s += res;
		s.pb(ch[1]);
		s.pb(ch[2]);
		x = press(s);
		cnt++;
		if (x == prev) res.pb(ch[2]);
		else if (x == prev + 1) res.pb(ch[0]);
		else res.pb(ch[1]);
		prev++;
	}
	res.pb(ch[0]);
	x = press(res);
	if (x == prev + 1) return res;
	res.pop_back();
	res.pb(ch[1]);
	x = press(res);
	if (x == prev + 1) return res;
	res.pop_back();
	res.pb(ch[2]);
	return res;
}

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