Submission #1142765

#	Time	Username	Problem	Language	Result	Execution time	Memory
1142765		xcalimar	Combo (IOI18_combo)	C++20	100 / 100	7 ms	480 KiB

combo

#include <bits/stdc++.h>
#include "combo.h"
#define REP(i, a, b) for(int i = a; i<b; i++)
#define all(v) v.begin(), v.end()
#define i64 long long
using namespace std;

const i64 MOD = 1000000007;

string guess_sequence(int n){
    //char a = 'A', b = 'B', x = 'X', y = 'Y';
    vector<string> a = {"A", "B", "X", "Y"};
    vector<string> c;
    string s = "";
    string f = "";
    string test = "AB";
    int ans = press(test);
    
    if(ans == 0){
        ans = press("X");
        
        if(ans == 0){
            s += 'Y';
            f += 'Y';
        }
        else{
            s += 'X';
            f += 'X';
        }
    } else{
        ans = press("A");
        
        if(ans == 0){
            s += 'B';
            f += 'B';
        }
        else{
            s += 'A';
            f += 'A';
        }
    }
    if(n==1)return s;
    REP(i, 0, a.size()){
        if(a[i] == f) continue;
        c.push_back(a[i]);
    }
    string t = "";
    while(s.size() < n-1){
        t += s + c[1];
        REP(i, 0, 3){
            t += s + c[0] + c[i];
        }
        ans = press(t);
        
        if(ans == s.size()){
            s += c[2];
        } else if(ans == s.size()+1){
            s += c[1];
        } else if(ans == s.size()+2){
            s += c[0];
        }
        t.clear();
    }
    test = s + c[0];
    ans = press(test);
    
    if(ans == n){
        s+=c[0];
        return s;
    }
    test = s + c[1];
    ans = press(test);
    
    if(ans == n){
        s+=c[1];
        return s;
    }
    return s+c[2];
}

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