Submission #144256

#	Time	Username	Problem	Language	Result	Execution time	Memory
144256		josiftepe	Combo (IOI18_combo)	C++14	100 / 100	48 ms	620 KiB

combo

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

std::string guess_sequence(int N) {
    vector<char> seq={'A','B','X','Y'};
    string s = "";
    int ab=press("AB");
    if(ab>=1)
    {
        int aa=press("A");
        if(aa==1)
        {
            s+='A';
        }
        else
        {
            s+='B';
        }
    }
    else
    {
        int xx=press("X");
        if(xx==1)
        {
            s+='X';
        }
        else
        {
            s+='Y';
        }
    }
    if(N == 1) {
        return s;
    }
    if(s[0] == 'A'){
        seq.erase(seq.begin());
    }
    else if(s[0] == 'B'){
        seq.erase(seq.begin() + 1);
    }
    else if(s[0] == 'X'){
        seq.erase(seq.begin() + 2);
    }
    else{
        seq.erase(seq.begin() + 3);
    }
    for(int i = 2; i < N; i++)
    {
        string prv=s+seq[0];
        string vtor=s+seq[1]+seq[2];
        string tret=s+seq[1]+seq[1];
        string cet=s+seq[1]+seq[0];
        string tmp = "";
        tmp += prv;
        tmp += vtor;
        tmp += tret;
        tmp += cet;
        int nxt=press(tmp);
        if(nxt>=1+i)s+=seq[1];
        else if(nxt==i)s+=seq[0];
        else s+=seq[2];
    }
    for(int i = 0; i < 2; i++){
        string tmp = s + seq[i];
        if(press(tmp) == N){
            return tmp;
        }
    }
    s += seq[2];
    return s;
}

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