Submission #1077363

#	Time	Username	Problem	Language	Result	Execution time	Memory
1077363		asdasdqwer	Combo (IOI18_combo)	C++14	100 / 100	24 ms	1920 KiB

combo

#include "combo.h"

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

std::string guess_sequence(int N) {
    string ret;
    int f1 = press("AB");
    if (f1 == 0) {
        f1 = press("X");
        if (f1 == 1) ret += "X";
        else ret += "Y";
    }

    else if (f1 == 1) {
        f1 = press("B");
        if (f1 == 1) ret = "B";
        else ret = "A";
    }

    else ret = "AB";

    vector<string> possible = {"A", "B", "X", "Y"};
    possible.erase(std::find(possible.begin(), possible.end(), string(1, ret[0])));
    while (ret.size()+1 < N) {
        string news = ret + possible[0];
        for (int i=0;i<3;i++) {
            news += ret + possible[1] + possible[i];
        }

        int code = press(news);

        if (code == ret.size()) ret += possible[2];
        else if (code == ret.size()+1) ret += possible[0];
        else ret += possible[1];
    }

    if (ret.size() == N) return ret;

    string news = ret + possible[0] + ret + possible[1];
    if (press(news) == N) {
        news = ret + possible[0];
        if (press(news) == N) ret += possible[0];
        else ret += possible[1];
    }

    else ret += possible[2];

    return ret;
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:25:25: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   25 |     while (ret.size()+1 < N) {
      |            ~~~~~~~~~~~~~^~~
combo.cpp:33:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   33 |         if (code == ret.size()) ret += possible[2];
      |             ~~~~~^~~~~~~~~~~~~
combo.cpp:34:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   34 |         else if (code == ret.size()+1) ret += possible[0];
      |                  ~~~~~^~~~~~~~~~~~~~~
combo.cpp:38:20: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   38 |     if (ret.size() == N) return ret;
      |         ~~~~~~~~~~~^~~~

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