Submission #777068

#	Time	Username	Problem	Language	Result	Execution time	Memory
777068		GusterGoose27	Combo (IOI18_combo)	C++17	100 / 100	26 ms	620 KiB

combo

#include "combo.h"

#include <bits/stdc++.h>

using namespace std;

string guess_sequence(int n) {
    string cur = "";
    char conv[4];
    conv[0] = 'A';
    conv[1] = 'B';
    conv[2] = 'X';
    conv[3] = 'Y';
    map<char, int> anticonv;
    for (int i = 0; i < 4; i++) anticonv[conv[i]] = i;
    int s;
    while (cur.size() < n) {
        if (cur.empty() || cur.size() == n-1) {
            if (press(cur+'A'+cur+'B') >= cur.size()+1) {
                if (press(cur+'A') == cur.size()+1) cur += 'A';
                else cur += 'B';
            }
            else {
                if (press(cur+'X') == cur.size()+1) cur += 'X';
                else cur += 'Y';
            }
            if (cur.size() == 1) s = anticonv[cur[0]];
            continue;
        }
        string res = cur+conv[(s+2)%4];
        for (int i = 1; i <= 3; i++) res += cur+conv[(s+3)%4]+conv[(s+i)%4];
        cur += conv[(s+1+press(res)-cur.size())%4];
    }
    return cur;
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:17:23: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   17 |     while (cur.size() < n) {
      |            ~~~~~~~~~~~^~~
combo.cpp:18:39: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   18 |         if (cur.empty() || cur.size() == n-1) {
      |                            ~~~~~~~~~~~^~~~~~
combo.cpp:19:40: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   19 |             if (press(cur+'A'+cur+'B') >= cur.size()+1) {
      |                 ~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~
combo.cpp:20:36: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   20 |                 if (press(cur+'A') == cur.size()+1) cur += 'A';
      |                     ~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~
combo.cpp:24:36: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |                 if (press(cur+'X') == cur.size()+1) cur += 'X';
      |                     ~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~
combo.cpp:16:9: warning: 's' may be used uninitialized in this function [-Wmaybe-uninitialized]
   16 |     int s;
      |         ^

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