This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <numeric>
#include <cmath>
#include <iterator>
#include <set>
#include <map>
#include <math.h>
#include <iomanip>
#include <unordered_set>
#include "combo.h"
using namespace std;
string guess_sequence(int n) {
    vector<string> moves;
    string s;
    int coins = press("AB");
    if (coins >= 1){
        if (press("A")){
            s = "A";
            moves = {"X", "B", "Y"};
        }
        else{
            s = "B";
            moves = {"A", "X", "Y"};
        }
    }
    else{
        if (press("X")){
            s = "X";
            moves = {"A", "B", "Y"};
        }
        else{
            s = "Y";
            moves = {"A", "B", "X"};
        }
    }
    
    if (n == 1) return s;
    while (s.size() < n - 1){
        string guess = s + moves[0] + s + moves[1] + moves[0] + s + moves[1] + moves[1] + s + moves[1] + moves[2];
        int coins = press(guess);
        if (coins == s.size()) s += moves[2];
        else if (coins == s.size() + 1) s += moves[0];
        else if (coins == s.size() + 2) s += moves[1];
    }
    for (int i = 0; i < 2; i++){
        string guess = s + moves[i];
        if (press(guess) == s.size() + 1) return guess;
    }
    return s + moves[2];
}
Compilation message (stderr)
combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:45:21: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   45 |     while (s.size() < n - 1){
      |            ~~~~~~~~~^~~~~~~
combo.cpp:49:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   49 |         if (coins == s.size()) s += moves[2];
      |             ~~~~~~^~~~~~~~~~~
combo.cpp:50:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   50 |         else if (coins == s.size() + 1) s += moves[0];
      |                  ~~~~~~^~~~~~~~~~~~~~~
combo.cpp:51:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   51 |         else if (coins == s.size() + 2) s += moves[1];
      |                  ~~~~~~^~~~~~~~~~~~~~~
combo.cpp:57:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   57 |         if (press(guess) == s.size() + 1) return guess;
      |             ~~~~~~~~~~~~~^~~~~~~~~~~~~~~| # | Verdict | Execution time | Memory | Grader output | 
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