Submission #1195125

#	Time	Username	Problem	Language	Result	Execution time	Memory
1195125		ezdp	Combo (IOI18_combo)	C++20	5 / 100	0 ms	396 KiB

combo

#include "combo.h"
#include <vector>
using namespace std;

string guess_sequence(int N){
	string G;
	{ // find initial character
		int t1 = press("AB");
		if(t1 >= 1){
			t1 = press("A");
			G += (t1 >= 1 ? 'A' : 'B');
		}
		else{
			t1 = press("X");
			G += (t1 >= 1 ? 'X' : 'Y');
		}
	}
	vector<string> letters;
	for(auto x : {"A", "B", "X", "Y"}){
		if(x[0] != G[0]) letters.push_back(x);
	}
	for(int i = 1; i < N - 1; i ++){
		string q;
		vector<string> vec;
		vec.push_back(letters[0]);
		vec.push_back(letters[1] + letters[0]);
		vec.push_back(letters[1] + letters[1]);
		vec.push_back(letters[1] + letters[2]);
		for(auto add : vec){
			q += G;
			q += add;
		}
		int p = press(q);
		if(p == (int)G.size() + 0) G += letters[2];
		else if(p == (int)G.size() + 1) G += letters[0];
		else if(p == (int)G.size() + 2) G += letters[1];
	}
	if(press(G + letters[0]) == N) return G + letters[0];
	if(press(G + letters[1]) == N) return G + letters[1];
	else return G + letters[2];
}

• Subtask 1: 5 / 5
• Subtask 2: 0 / 95