Submission #971279

#	Time	Username	Problem	Language	Result	Execution time	Memory
971279		codefox	Combo (IOI18_combo)	C++14	0 / 100	74 ms	444 KiB

combo

#include<bits/stdc++.h>
#include "combo.h"

using namespace std;

array<char, 4> arr = {'A', 'B', 'Y', 'X'};

string guess_sequence(int N) {
    char f = 'N';
    for (int i = 0; i < 3; i++)
    {
        string st = "";
        st += arr[i];
        if (press(st))
        {
            f = arr[i];
            break;
        }
    }
    if (f=='N') f = 'X';
    
    string s = "";
    s += f;
    for (int i = 1; i < N; i++)
    {
        if (f == 'A') s+='B';
        else s+='A';
    }
    int j = press(s);

    while (j != N)
    {
        string ss=  "";
        for (int i = 0; i < N; i++)
        {
            if (i < j) ss+=s[i];
            else if (i==j && f != 'X') ss+='X';
            else if (i==j && f=='X') ss+='Y';
            else if (f =='A') ss+='B';
            else ss += 'A';
        }
        int nj = press(ss);
        if (nj==j)
        {
            if (f == 'X' || f == 'Y') ss[nj] = 'B';
            else ss[nj] = 'Y';
            nj++;
        }
        s = ss;
        j=nj;
    }

    return s;
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 95