Submission #362338

#	Time	Username	Problem	Language	Result	Execution time	Memory
362338		usuyus	Combo (IOI18_combo)	C++14	100 / 100	43 ms	560 KiB

combo

#include "combo.h"
using namespace std;

string all = "ABXY";

string guess_sequence(int n) {
	string res; int beg = -1;
	
	if (press("AB")) {
		if (press("A")) beg = 0;
		else beg = 1;
	} else {
		if (press("X")) beg = 2;
		else beg = 3;
	}

	res += all[beg];
	if (n == 1) return res;
	
	char x = all[(beg+1)%4], y = all[(beg+2)%4], z = all[(beg+3)%4];

	for (int i=2; i<n; i++) {
		int tmp = press(res+x + res+y+x + res+y+y + res+y+z);
		if (tmp == i-1) res += z;
		else if (tmp == i) res += x;
		else res += y;
	}

	if (press(res+x) == n) res += x;
	else if (press(res+y) == n) res += y;
	else res += z;

	return res;
}

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