Submission #76355

#	Time	Username	Problem	Language	Result	Execution time	Memory
76355		arock	Combo (IOI18_combo)	C++14	0 / 100	2 ms	200 KiB

combo

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

std::string guess_sequence(int N) {

	char first = press("AB") == 0? "YA"[press("X")]:
	                               "BA"[press("A")];

	char a, b, c;
	if(first == 'A') a = 'B', b = 'X', c = 'Y';
	if(first == 'B') a = 'A', b = 'X', c = 'Y';
	if(first == 'X') a = 'A', b = 'B', c = 'Y';
	if(first == 'Y') a = 'A', b = 'B', c = 'X';

	std::string S(1, first);
	while(S.length() + 2 <= N) {
		int coins = press(S + a + a + S + a + b + S + b + a) - S.length();
		if (coins == 0) {
			S += c;
		} else if (coins == 1) {
			coins = press(S + b + c) - S.length();
			if (coins == 0) {
				S += a, S += c;
			} else if (coins == 1) {
				S += b, S += b;
			} else if (coins == 2) {
				S += b, S += c;
			}
		} else if (coins == 2) {
			coins = press(S + a + b) - S.length();
			if (coins == 0) {
				S += b, S += a;
			} else if (coins == 1) {
				S += a, S += a;
			} else if (coins == 2) {
				S += a, S += b;
			}
		}
	}

	if (S.length() < N) {
		if (press(S + a) - S.length() == 1) {
			S += a;
		} else if(press(S + b) - S.length() == 1) {
			S += b;
		} else {
			S += c;
		}
	}

	return S;
}

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(S.length() + 2 <= N) {
      |        ~~~~~~~~~~~~~~~^~~~
combo.cpp:42:17: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   42 |  if (S.length() < N) {
      |      ~~~~~~~~~~~^~~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 95