Submission #1191537

#	Time	Username	Problem	Language	Result	Execution time	Memory
1191537		vidux	Combo (IOI18_combo)	C++17	100 / 100	7 ms	484 KiB

combo

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

// #define LOCAL

typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int, int> pii;

#ifdef LOCAL
int press(string p) {
	cout << p << ": ";
	int x; cin >> x;
	return x;
}
#else
#include "combo.h"
#endif

string guess_sequence(int n) {
	string a;
	string all = "ABXY";
	string cur = "ABXY";
	{ // Find first
		int ab = press("AB");
		if (ab) {
			int x = press(string(1, 'A'));
			if (x) a = 'A', cur = "BXY";
			else   a = 'B', cur = "AXY";
		}
		else {
			int x = press(string(1, 'X'));
			if (x) a = 'X', cur = "ABY";
			else   a = 'Y', cur = "ABX";
		}
	}

    if (n == 1) return a;

	{ // Find middle
		for (int i = 1; i < n-1; i++) {
			string guess = a+cur[0] + a+cur[1]+cur[0] + a+cur[1]+cur[1] + a+cur[1]+cur[2];
			int score = press(guess);
			if (score == i+1) a += cur[0];
			if (score == i+2) a += cur[1];
			if (score == i+0) a += cur[2];
		}
	}
	
	{ // Find last
		if (press(a + cur[0]) == n) a += cur[0];
		else if (press(a + cur[1]) == n) a += cur[1];
		else a += cur[2];
	}

	return a;
}

#ifdef LOCAL
int main() {
	int n; cin >> n;
	cout << guess_sequence(n) << endl;
	return 0;
}
#endif

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