Submission #478252

#	Time	Username	Problem	Language	Result	Execution time	Memory
478252		ColourAttila	Combo (IOI18_combo)	C++17	100 / 100	38 ms	584 KiB

combo

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

string guess_sequence(int N)
{
    string mo = "";
    int first = press("AB"), second;

    if(first) {
        second = press("A");
        if(second) mo = "A";
        else mo = "B";
    }
    else {
        second = press("X");
        if(second) mo = "X";
        else mo = "Y";
    }

    if(N == 1) return mo;

    string elements = "ABXY";
    vector<char> notFirst;
    for(char c : elements) {
        if(c != mo[0]) notFirst.push_back(c);
    }

    for(int i = 1; i < N - 1; i++) {
        string temp = "";
        temp += mo + notFirst[0] + notFirst[0];
        temp += mo + notFirst[0] + notFirst[1];
        temp += mo + notFirst[0] + notFirst[2];
        temp += mo + notFirst[1];

        int ans = press(temp);
        if(ans == i) {
            mo += notFirst[2];
        }
        else if(ans == i+1) {
            mo += notFirst[1];
        }
        else {
            mo += notFirst[0];
        }
    }

    bool b = false;
    for(int i = 0; i < 2; i++) {
        int temp = press(mo + notFirst[i]);
        if(temp == N) {
            b = true;
            mo += notFirst[i];
            break;
        }
    }

    if(!b) mo += notFirst[2];

    return mo;
}

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