Submission #421428

#	Time	Username	Problem	Language	Result	Execution time	Memory
421428		alireza_kaviani	Combo (IOI18_combo)	C++11	97 / 100	43 ms	604 KiB

combo

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

vector<string> vec = {"A" , "B" , "X" , "Y"} , valid;

string guess_sequence(int n){
	string cur = "";
	for(int i = 0 ; i < 3 ; i++){
		if(press(vec[i]) == 1){
			cur = vec[i];
			break;
		}
	}
	if(cur.size() == 0)	cur = vec[3];
	if(n == 1)	return cur;
	for(string i : vec){
		if(i != cur){
			valid.push_back(i);
		}
	}
	for(int i = 1 ; i + 1 < n ; i++){
		string ask = cur + valid[1];
		for(string j : valid)	ask += cur + valid[2] + j;
		int res = press(ask);
		for(int j = 0 ; j < 3 ; j++){
			if(res == i + j)	cur += valid[j];
		}
	}
	for(int i = 0 ; i < 2 ; i++){
		if(press(cur + valid[i]) == n)	return cur + valid[i];
	}
	return cur + valid[2];
}

• Subtask 1: 5 / 5
• Subtask 2: 92 / 95