Submission #485446

#	Time	Username	Problem	Language	Result	Execution time	Memory
485446		status_coding	Combo (IOI18_combo)	C++14	100 / 100	40 ms	564 KiB

combo

#include "combo.h"

using namespace std;

char findFirst()
{
    if(press("AB"))
    {
        if(press("A"))
            return 'A';
        else
            return 'B';
    }
    else
    {
        if(press("X"))
            return 'X';
        else
            return 'Y';
    }
}

string guess_sequence(int n)
{
    string ans;
    ans += findFirst();

    if(n == 1)
        return ans;

    string alphabet = "ABXY";
    char first=0, second=0, third=0;

    for(char ch : alphabet)
    {
        if(ch == ans[0])
            continue;

        if(!first)
            first=ch;
        else if(!second)
            second=ch;
        else
            third=ch;
    }

    for(int i=2;i<n;i++)
    {
        string q;

        q+=ans;
        q+=first;

        q+=ans;
        q+=second;
        q+=first;

        q+=ans;
        q+=second;
        q+=second;

        q+=ans;
        q+=second;
        q+=third;

        int x=press(q);

        if(x == i)
            ans += first;
        if(x == i+1)
            ans += second;
        if(x == i-1)
            ans += third;
    }

    string q=ans+first;

    if(press(q) == n)
        return q;

    q=ans+second;
    if(press(q) == n)
        return q;

    q=ans+third;
    return q;
}

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