Submission #113891

#	Time	Username	Problem	Language	Result	Execution time	Memory
113891		antimirage	Combo (IOI18_combo)	C++14	100 / 100	41 ms	600 KiB

combo

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

#define fr first
#define sc second
#define mk make_pair
#define pb push_back
#define all(s) s.begin(), s.end()

using namespace std;

string s;

string guess_sequence (int n) 
{  
	int res = press("AB");
	
	char ch1, ch2, ch3;
	
	if (res){
		if (press("A") )
			s += 'A';
		else
			s += 'B';
	}
	else{
		if (press("X") )
			s += 'X';
		else
			s += 'Y';
	}
	if (s[0] == 'A')
		ch1 = 'B', ch2 = 'X', ch3 = 'Y';
	
	if (s[0] == 'B')
		ch1 = 'A', ch2 = 'X', ch3 = 'Y';
	
	if (s[0] == 'X')
		ch1 = 'B', ch2 = 'A', ch3 = 'Y';
	
	if (s[0] == 'Y')
		ch1 = 'B', ch2 = 'X', ch3 = 'A';
	
	for (int i = 1; i < n; i++)
	{
		if (i < n - 1){
			int res = press( s + ch1 + s + ch2 + ch1 + s + ch2 + ch2 + s + ch2 + ch3 ) - i;
			
			if (res == 0)
				s += ch3;
			else if (res == 1)
				s += ch1;
			else
				s += ch2;
		}
		else{
			int res = press(s + ch1) - i;
			
			if (res)
				s += ch1;
			else{
				res = press(s + ch2) - i;
				
				if (res)
					s += ch2;
				else
					s += ch3;
			}	
		}
	}
	return s;
}

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