Submission #97304

#	Time	Username	Problem	Language	Result	Execution time	Memory
97304		E869120	Combo (IOI18_combo)	C++14	100 / 100	41 ms	596 KiB

combo

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

string G = "ABXY", I;

string rev(int p1, int p2) {
	return I.substr(p1, 1) + I.substr(p2, 1);
}

string guess_sequence(int N) {
	// At first, you should find the 1st letter
	int F1 = press("AB"), fir = 0;
	if (F1 >= 1) {
		int F2 = press("A");
		if (F2 == 1) fir = 0; else fir = 1;
	}
	else {
		int F2 = press("X");
		if (F2 == 1) fir = 2; else fir = 3;
	}
	
	for (int i = 0; i < 4; i++) { if (i != fir) I += G[i]; }
	
	// Second, you should find 2 - (N-1)th letter
	string S = ""; S += G[fir];
	
	while ((int)S.size() <= N - 2) {
		string query = S + rev(0, 0) + S + rev(0, 1) + S + rev(1, 2);
		int F3 = press(query);
		if (F3 >= S.size() + 2) {
			string query2 = S + rev(0, 0);
			int F4 = press(query2);
			if (F4 == S.size() + 2) S += rev(0, 0);
			else if (F4 == S.size() + 1) S += rev(0, 1);
			else if (F4 == S.size() + 0) S += rev(1, 2);
		}
		else if (F3 == S.size() + 1) {
			string query2 = S + rev(1, 0);
			int F4 = press(query2);
			if (F4 == S.size() + 2) S += rev(1, 0);
			else if (F4 == S.size() + 1) S += rev(1, 1);
			else if (F4 == S.size() + 0) S += rev(0, 2);
		}
		else {
			S += I[2];
		}
	}
	
	if (S.size() == N - 1) {
		for (int i = 0; i < 2; i++) {
			string query3 = S + I.substr(i, 1);
			int F5 = press(query3);
			if (F5 == N) { S += I[i]; break; }
		}
		if (S.size() == N - 1) S += I[2];
	}
	return S;
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:31:10: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   31 |   if (F3 >= S.size() + 2) {
      |       ~~~^~~~~~~~~~~~~~~
combo.cpp:34:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   34 |    if (F4 == S.size() + 2) S += rev(0, 0);
      |        ~~~^~~~~~~~~~~~~~~
combo.cpp:35:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   35 |    else if (F4 == S.size() + 1) S += rev(0, 1);
      |             ~~~^~~~~~~~~~~~~~~
combo.cpp:36:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |    else if (F4 == S.size() + 0) S += rev(1, 2);
      |             ~~~^~~~~~~~~~~~~~~
combo.cpp:38:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |   else if (F3 == S.size() + 1) {
      |            ~~~^~~~~~~~~~~~~~~
combo.cpp:41:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   41 |    if (F4 == S.size() + 2) S += rev(1, 0);
      |        ~~~^~~~~~~~~~~~~~~
combo.cpp:42:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   42 |    else if (F4 == S.size() + 1) S += rev(1, 1);
      |             ~~~^~~~~~~~~~~~~~~
combo.cpp:43:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |    else if (F4 == S.size() + 0) S += rev(0, 2);
      |             ~~~^~~~~~~~~~~~~~~
combo.cpp:50:15: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   50 |  if (S.size() == N - 1) {
      |      ~~~~~~~~~^~~~~~~~
combo.cpp:56:16: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   56 |   if (S.size() == N - 1) S += I[2];
      |       ~~~~~~~~~^~~~~~~~

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