Submission #102701

#	Time	Username	Problem	Language	Result	Execution time	Memory
102701		bert30702	Combo (IOI18_combo)	C++17	100 / 100	50 ms	572 KiB

combo

#include <bits/stdc++.h>
#include "combo.h"
using namespace std;
//int press(string s) {
//	cout << s << endl;
//	int k; cin >> k;
//	return k;
//}
string guess_sequence(int N) {
	if(N == 1) {
		string a = "A"; int A = press(a);
		string b = "B"; int B = press(b);
		string x = "X"; int X = press(x);
		string y = "Y";
		     if(A == 1) return a;
		else if(B == 1) return b;
		else if(X == 1) return x;
		else            return y;
	}
	char c[4] = {'A', 'B', 'X', 'Y'};
	bool GG[4] = {};
	string a = "A"; 
	string b = "B";
	string x = "X";
	string y = "Y";
	int AB = press(a + b);
	string cur;
	if(AB >= 1) {
		int k = press(a);
		if(k == 1) cur = a, GG[0] = true;
		else       cur = b, GG[1] = true;
	}
	else {
		int k = press(x);
		if(k == 1) cur = x, GG[2] = true;
		else       cur = y, GG[3] = true;
	} 
	string OK;
	for(int j = 0; j < 4; j ++) if(!GG[j]) OK.push_back(c[j]); 
	for(int i = 2; i < N; i ++) {
		string ask = 
			cur + OK[0] + 
			cur + OK[1] + OK[0] + 
			cur + OK[1] + OK[1] + 
			cur + OK[1] + OK[2];
		int k = press(ask);
		if(k == cur.size() + 0) cur += OK[2];
		if(k == cur.size() + 1) cur += OK[0];
		if(k == cur.size() + 2) cur += OK[1];
	}
	assert(cur.size() == N - 1);
	if(press(cur + OK[0]) == N) return cur + OK[0];
	if(press(cur + OK[1]) == N) return cur + OK[1];
	else                        return cur + OK[2];
}
//int main() {
//	cout << "! " << guess_sequence(6);
//}
//// ABXXXY

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:47:8: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   47 |   if(k == cur.size() + 0) cur += OK[2];
      |      ~~^~~~~~~~~~~~~~~~~
combo.cpp:48:8: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   48 |   if(k == cur.size() + 1) cur += OK[0];
      |      ~~^~~~~~~~~~~~~~~~~
combo.cpp:49:8: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   49 |   if(k == cur.size() + 2) cur += OK[1];
      |      ~~^~~~~~~~~~~~~~~~~
In file included from /usr/include/c++/10/cassert:44,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:33,
                 from combo.cpp:1:
combo.cpp:51:20: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   51 |  assert(cur.size() == N - 1);
      |         ~~~~~~~~~~~^~~~~~~~

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