Submission #1072585

#	Time	Username	Problem	Language	Result	Execution time	Memory
1072585		Rigobertus	Combo (IOI18_combo)	C++17	100 / 100	26 ms	1972 KiB

combo

#include <iostream>
#include <algorithm>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <string>
//#define int long long
#include "combo.h"
using namespace std;

string guess_sequence(int n) {
    string c[4] = {"A", "B", "X", "Y"};
    string s;
    if (press("AB")) {
        s = "B";
        if (press("A")) {
            s = "A";
        }
    }
    else {
        s = "X";
        if (press("Y")) {
            s = "Y";
        }
    }
    vector<int> a;
    for (int i = 0; i < 4; i++) {
        if (c[i] != s) {
            a.push_back(i);
        }
    }

    if (n == 1) {
        return s;
    }

    while (s.size() < n - 1) {
        string p = s + c[a[0]];
        for (int i = 0; i < 3; i++) {
            p += s + c[a[1]] + c[a[i]];
        }
        int x = press(p);
        if (x == s.size()) {
            s += c[a[2]];
        }
        else if (x == s.size() + 1) {
            s += c[a[0]];
        }
        else {
            s += c[a[1]];
        }
    }
    string ans = s;
    if (press(s + "A" + s + "B") == n) {
        ans = s + "A";
        if (press(s + "B") == n) {
            ans = s + "B";
        }
    }
    else {
        ans = s + "X";
        if (press(s + "Y") == n) {
            ans = s + "Y";
        }
    }
    return ans;
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:38:21: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   38 |     while (s.size() < n - 1) {
      |            ~~~~~~~~~^~~~~~~
combo.cpp:44:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   44 |         if (x == s.size()) {
      |             ~~^~~~~~~~~~~
combo.cpp:47:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   47 |         else if (x == s.size() + 1) {
      |                  ~~^~~~~~~~~~~~~~~

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