Submission #82756

#	Time	Username	Problem	Language	Result	Execution time	Memory
82756		hugo_pm	Combo (IOI18_combo)	C++14	100 / 100	65 ms	552 KiB

combo

#include "combo.h"
using namespace std;

string S;
int N;
char ff;
string cc = "ABXY";
string test = "";

string guess_sequence(int locN)
{
    N = locN;
    int a1 = press("AB");

    if (a1 == 0) {
        int a2 = press("X");
        if (a2 == 0) S.push_back('Y');
        else S.push_back('X');
    } else {
        int a2 = press("A");
        if (a2 == 0) S.push_back('B');
        else S.push_back('A');
    }

    if (N == 1) return S;
    for (char c : cc) if (c != S[0]) test.push_back(c);

    for (int i = 1; i < N-1; ++i) {
        string p;
        p.append(S);
        p.push_back(test[0]);
        for (char c : test) {
            p.append(S);
            p.push_back(test[1]);
            p.push_back(c);
        }
        int cc = press(p);
        if (cc == i) {
            S.push_back(test[2]);
        } else if (cc == i+1) {
            S.push_back(test[0]);
        } else {
            S.push_back(test[1]);
        }
    }

    for (int i = 0; i < 2; ++i) {
        if (press(S+test[i]) == N) return S+test[i];
    }
    return S+test[2];
}

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