Submission #298019

#	Time	Username	Problem	Language	Result	Execution time	Memory
298019		miss_robot	Combo (IOI18_combo)	C++14	100 / 100	39 ms	596 KiB

combo

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

#pragma GCC optimize("O3")

using namespace std;

string guess_sequence(int N){
	string p, t, test;
	int ans;
	if(press("AB")){
		if(press("A")) p = "A", t = "BXY";
		else p = "B", t = "AXY";
	}
	else{
		if(press("X")) p = "X", t = "ABY";
		else p = "Y", t = "ABX";
	}
	if(N == 1) return p;
	for(int i = 1; i < N-1; i++){
		test = p; test += t[0];
		test += p; test += t[1]; test += t[0];
		test += p; test += t[1]; test += t[1];
		test += p; test += t[1]; test += t[2];
		ans = press(test)-i;
		if(ans == 2) p += t[1];
		else if(ans) p += t[0];
		else p += t[2];
	}
	p += t[0];
	if(press(p) != N){
		p.pop_back();
		p += t[1];
		if(press(p) != N) p.pop_back(), p += t[2];
	}
	return p;
}

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