Submission #640158

#	Time	Username	Problem	Language	Result	Execution time	Memory
640158		ymm	Combo (IOI18_combo)	C++17	100 / 100	34 ms	588 KiB

combo

#include "combo.h"

#include <bits/stdc++.h>
#define Loop(x,l,r) for (ll x = (l); x < (r); ++x)
#define LoopR(x,l,r) for (ll x = (r)-1; x >= (l); --x)
typedef long long ll;
typedef std::pair<int, int> pii;
typedef std::pair<ll , ll > pll;
using namespace std;

#define INIT(x) do { swap(a[0], a[x]); s += a[0]; } while(0)
std::string guess_sequence(int N) {
	string s = "";
	char a[4] = {'A', 'B', 'X', 'Y'};
	{
		if (press("AB"))
			if (press("A"))
				INIT(0);
			else
				INIT(1);
		else
			if (press("X"))
				INIT(2);
			else
				INIT(3);
	}
	if (N == 1)
		return s;
	Loop (i,1,N-1) {
		int x = press(s + a[2] + s + a[3] + a[1] + s + a[3] + a[2] + s + a[3] + a[3]) - i;
		if (x == 0)
			s += a[1];
		else if (x == 1)
			s += a[2];
		else /* if (x == 2) */
			s += a[3];
	}
	{
		if (press(s + a[1]) == N)
			s += a[1];
		else if (press(s + a[2]) == N)
			s += a[2];
		else
			s += a[3];
	}
	return s;
}

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