Submission #807809

#	Time	Username	Problem	Language	Result	Execution time	Memory
807809		math_rabbit_1028	Combo (IOI18_combo)	C++14	100 / 100	34 ms	500 KiB

combo

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

int n;
string solve(string s, string t, string u, string v) {
    string ans, query;
    ans = s;
    for (int i = 2; i < n; i++) {
        query = "";

        query += ans;
        query += t;
        query += t;

        query += ans;
        query += t;
        query += u;

        query += ans;
        query += t;
        query += v;

        query += ans;
        query += u;

        int res = press(query);
        if (res == i + 1) ans += t;
        if (res == i) ans += u;
        if (res == i - 1) ans += v;
    }
    query = ans + t;
    if (press(query) == n) return query;
    query = ans + u;
    if (press(query) == n) return query;
    query = ans + v;
    return query;
}

std::string guess_sequence(int N) {
    n = N;
    int ab = press("AB");
    if (ab) {
        int a = press("A");
        if (a == 1) {
            if (n == 1) return "A";
            return solve("A", "B", "X", "Y");
        }
        else {
            if (n == 1) return "B";
            return solve("B", "A", "X", "Y");
        }
    }
    else {
        int x = press("X");
        if (x == 1) {
            if (n == 1) return "X";
            return solve("X", "A", "B", "Y");
        }
        else {
            if (n == 1) return "Y";
            return solve("Y", "A", "B", "X");
        }
    }
}

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