Submission #639974

#	Time	Username	Problem	Language	Result	Execution time	Memory
639974		haxorman	Combo (IOI18_combo)	C++14	100 / 100	37 ms	588 KiB

combo

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

string guess_sequence(int N) {
	string s;
	vector<string> letters = {"A", "B", "X", "Y"};
	
	string guess = "AB";
	int coins = press(guess);

	if (coins == 2) {
		s = "AB";
	}
	else if (coins == 1) {
		guess = "A";
		coins = press(guess);

		if (coins == 1) {
			s = "A";
		}
		else {
			s = "B";
		}
	}
	else {
		guess = "X";
		coins = press(guess);
		
		if (coins == 1) {
			s = "X";
		}
		else {
			s = "Y";
		}
	}
	

	for (int i = 0; i < 4; ++i) {
		if (letters[i].back() == s[0]) {
			letters.erase(letters.begin() + i);
			break;
		}
	}

	while (s.size() < N) {
		guess.clear();
		guess += s + letters[0];
		// YB + A
		// YB + BA / YB + BB / YB + BX
		// YBAYBBAYBBBYBBX

		if (s.size() < N - 1) {
			for (int i = 0; i < 3; ++i) {
				guess += s + letters[1] + letters[i];
			}
		}
		else {
			guess += s + letters[1];
		}
		
		//cout << s << ' ' << guess << "\n";
		coins = press(guess);
		if (coins == s.size()) {
			s += letters[2];
		}
		else if (s.size() == N - 1) {
			guess = s + letters[0];

			coins = press(guess);
			if (coins == s.size()) {
				s += letters[1];
			}
			else {
				s += letters[0];
			}
		}
		else if (coins == s.size() + 1) {
			s += letters[0];
		}
		else {
			s += letters[1];
		}
	}
	return s;
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:46:18: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   46 |  while (s.size() < N) {
      |         ~~~~~~~~~^~~
combo.cpp:53:16: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   53 |   if (s.size() < N - 1) {
      |       ~~~~~~~~~^~~~~~~
combo.cpp:64:13: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   64 |   if (coins == s.size()) {
      |       ~~~~~~^~~~~~~~~~~
combo.cpp:67:21: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   67 |   else if (s.size() == N - 1) {
      |            ~~~~~~~~~^~~~~~~~
combo.cpp:71:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   71 |    if (coins == s.size()) {
      |        ~~~~~~^~~~~~~~~~~
combo.cpp:78:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   78 |   else if (coins == s.size() + 1) {
      |            ~~~~~~^~~~~~~~~~~~~~~

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