Submission #1020749

#	Time	Username	Problem	Language	Result	Execution time	Memory
1020749		ZanP	Combo (IOI18_combo)	C++14	100 / 100	25 ms	1872 KiB

combo

#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
using namespace std;
 
int press(string p);
// {
//     cout << p << '\n';
//     int a; cin >> a;
//     return a;
// }
 
int n;
string z;
string p;
void make_bases()
{
    if (z[0] == 'A') {
        p = "XYB";
    }
    else if (z[0] == 'B') {
        p = "AXY";
    }
    else if (z[0] == 'X') {
        p = "ABY";
    }
    else if (z[0] == 'Y') {
        p = "ABX";
    }
}

string guess_sequence(int N)
{
    n = N;
    z.reserve(n);
    int a = press("AB");
    if (a == 2) { z = "AB"; }
    else if (a == 1) {
        if (press("A")) {
            z = "A";
        }
        else {
            z = "B";
        }
    }
    else {
        if (press("X")) {
            z = "X";
        }
        else {
            z = "Y";
        }
    }
    make_bases();
    while (z.size() < n - 1)
    {
        string ask = z;
        ask.push_back(p[0]);
        for (int i = 0; i < 3; i++) {
            ask.append(z);
            ask.push_back(p[1]);
            ask.push_back(p[i]);
        }
        a = press(ask);
        if (a == z.size())
        {
            z.push_back(p[2]);
        }
        else if (a == z.size() + 1)
        {
            z.push_back(p[0]);
        }
        else
        {
            z.push_back(p[1]);
        }
    }
    if (z.size() == n) { return z; }
    for (int i = 0; i < 2; i++)
    {
        string ask = z;
        ask.push_back(p[i]);
        a = press(ask);
        if (a == n) return ask;
    }
    z.push_back(p[2]);
    return z;
}

// int main()
// {
//     int x; cin >> x; cout << guess_sequence(x) << '\n';
//     return 0;
// }

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:56:21: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   56 |     while (z.size() < n - 1)
      |            ~~~~~~~~~^~~~~~~
combo.cpp:66:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   66 |         if (a == z.size())
      |             ~~^~~~~~~~~~~
combo.cpp:70:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   70 |         else if (a == z.size() + 1)
      |                  ~~^~~~~~~~~~~~~~~
combo.cpp:79:18: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   79 |     if (z.size() == n) { return z; }
      |         ~~~~~~~~~^~~~

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