Submission #864038

#	Time	Username	Problem	Language	Result	Execution time	Memory
864038		dpsaveslives	Combo (IOI18_combo)	C++17	100 / 100	12 ms	1732 KiB

combo

#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
 
string guess_sequence(int N){
    vector<int> mp = {'A','B','X','Y'};
    string s = ""; int p;
    int r = press("AB");
    if(r == 0){
        r = press("X");
        if(r == 0){
            s += "Y";
            p = 3;
        }
        else{
            s += "X";
            p = 2;
        }
    }
    else if(r == 1){
        r = press("A");
        if(r == 0){
            s += "B";
            p = 1;
        }
        else{
            s += "A";
            p = 0;
        }
    }
    else{
        p = 0;
        s += "A";
    }
    if(N == 1) return s; 
    for(int i = 1;i<=N-2;++i){
        string cur = "";
        for(int j = 0;j<4;++j){
            if(j != p){
                cur += s; cur += mp[(p+1)%4];
                cur += mp[j];
            }
        }
        cur += s; cur += mp[(p+2)%4];
        int r = press(cur);
        if(r == i){
            s += mp[(p+3)%4];
        }
        else if(r == i+1){
            s += mp[(p+2)%4];
        }
        else{
            s += mp[(p+1)%4];
        }
    }
    string cur = ""; cur += s; cur += mp[(p+1)%4];
    r = press(cur);
    if(r == N) return cur;
    string newcur = ""; newcur += s; newcur += mp[(p+2)%4];
    r = press(newcur);
    if(r == N) return newcur;
    s += mp[(p+3)%4];
    return s;
}

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