Submission #939381

#	Time	Username	Problem	Language	Result	Execution time	Memory
939381		ifateen	Combo (IOI18_combo)	C++14	97 / 100	13 ms	1956 KiB

combo

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

string guess_sequence(int N) {
    string ans;
    vector<string> possible = {"A", "B", "X", "Y"};
    int a = press("A");
    if (a) {
        possible = {"B", "X", "Y", "A"};
        ans += 'A';
    } else {
        int b = press("B");
        if (b) {
            possible = {"A", "X", "Y", "B"};
            ans += 'B';
        } else {
            int x = press("X");
            if (x) {
                possible = {"A", "B", "Y", "X"};
                ans += 'X';
            } else {
                ans += 'Y';
            }
        }
    }
    while (ans.size() < N - 1) {
        string query = ans + possible[1] + ans + possible[2] + possible[0] + ans + possible[2] + possible[1] + ans + possible[2] + possible[2];
        int ret = press(query);
        if (ret == ans.size()) {
            ans += possible[0];
        } else if (ret == ans.size() + 1) {
            ans += possible[1];
        } else {
            ans += possible[2];
        }
    }
    if (ans.size() == N) return ans;
    int zero = press(ans + possible[0]);
    if (zero == N) return (ans += possible[0]);
    int one = press(ans + possible[1]);
    if (one == N) return (ans += possible[1]);
    return (ans += possible[2]);
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:27:23: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   27 |     while (ans.size() < N - 1) {
      |            ~~~~~~~~~~~^~~~~~~
combo.cpp:30:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 |         if (ret == ans.size()) {
      |             ~~~~^~~~~~~~~~~~~
combo.cpp:32:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   32 |         } else if (ret == ans.size() + 1) {
      |                    ~~~~^~~~~~~~~~~~~~~~~
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 (ans.size() == N) return ans;
      |         ~~~~~~~~~~~^~~~

• Subtask 1: 5 / 5
• Subtask 2: 92 / 95