Submission #436403

#	Time	Username	Problem	Language	Result	Execution time	Memory
436403		stoyan_malinin	Combo (IOI18_combo)	C++14	30 / 100	67 ms	456 KiB

combo

#include <algorithm>
#include <iostream>
#include <vector>
#include <string>

#include "combo.h"
#ifdef __LOCAL
#include "grader.cpp"
#endif // __LOCAL

using namespace std;

char extend(string &ans)
{
    vector <char> options = {'A', 'B', 'X', 'Y'};
    if(ans.size()!=0)
        options.erase(find(options.begin(), options.end(), ans[0]));

    if(ans.size()==0)
    {
        if(press("AB")>=1)
        {
            if(press("A")>=1) return 'A';
            return 'B';
        }
        else
        {
            if(press("X")>=1) return 'X';
            return 'Y';
        }
    }
    else
    {
        int res = press(ans+options[0]+ans+options[1]);
        if(res==ans.size()) return options[2];

        res = press(ans+options[0]);
        if(res==ans.size()) return options[1];

        return options[0];
    }
}

string guess_sequence(int N)
{
    string ans = "";
    for(int i = 0;i<N;i++) ans += extend(ans);

    return ans;
}

Compilation message (stderr)

combo.cpp: In function 'char extend(std::string&)':
combo.cpp:35:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   35 |         if(res==ans.size()) return options[2];
      |            ~~~^~~~~~~~~~~~
combo.cpp:38:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |         if(res==ans.size()) return options[1];
      |            ~~~^~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 25 / 95