Submission #587860

#	Time	Username	Problem	Language	Result	Execution time	Memory
587860		IvanJ	Combo (IOI18_combo)	C++17	100 / 100	37 ms	604 KiB

combo

#include "combo.h"
#include<bits/stdc++.h>

#define all(a) (a).begin(), (a).end()

using namespace std;

string guess_sequence(int n) {
	string p = "", S = "";
	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;
  
	set<string> q;
	q.insert("A"), q.insert("B"), q.insert("X"), q.insert("Y");
	q.erase(S);
	vector<string> v(all(q));
	for(int i = 1;i < n - 1;i++) {
		p = S + v[0];
		for(int j = 0;j < 3;j++) 
			p += S + v[1] + v[j];
		int x = press(p), m = S.size();
		if(x == m + 1) S += v[0];
		if(x == m + 2) S += v[1];
		if(x == m) S += v[2];
	}
	if(press(S + v[0]) == n) S += v[0];
	else if(press(S + v[1]) == n) S += v[1];
	else S += v[2];
	return S;
}

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