Submission #482529

#	Time	Username	Problem	Language	Result	Execution time	Memory
482529		M_W	Combo (IOI18_combo)	C++17	100 / 100	36 ms	612 KiB

combo

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

string guess_sequence(int N){
	char init;
	if(press("AB") >= 1){
		if(press("A") == 1) init = 'A';
		else init = 'B';
	}
	else{
		if(press("X") == 1) init = 'X';
		else init = 'Y';
	}
	if(N == 1){
		string tmp(1, init);
		return tmp;
	}
	string s(N * 4, init);
	vector<char> v;
	if(init != 'A') v.push_back('A');
	if(init != 'B') v.push_back('B');
	if(init != 'X') v.push_back('X');
	if(init != 'Y') v.push_back('Y');
	
	for(int i = 1; i < N - 1; i++){
		s[i] = v[0];
		s[N + i] = v[0];
		s[N * 2 + i] = v[0];
		s[N * 3 + i] = v[1];
		
		s[i + 1] = v[0];
		s[N + i + 1] = v[1];
		s[N * 2 + i + 1] = v[2];
		
		int ret = press(s);
		int c;
		if(ret == i + 2) c = 0;
		else if(ret == i + 1) c = 1;
		else c = 2;
		
		for(int j = 0; j < 4; j++) s[N * j + i] = v[c];
	}
	int c2;
	s[N * 2 - 1] = s[N * 3 - 1] = s[N * 4 - 1] = init;
	s[N - 1] = v[0];
	if(press(s) == N) c2 = 0;
	else{
		s[N - 1] = v[1];
		if(press(s) == N) c2 = 1;
		else c2 = 2;
	}
	s[N - 1] = v[c2];
	string ans(N, init);
	for(int i = 0; i < N; i++) ans[i] = s[i];
	return ans;
}

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