Submission #333577

#	Time	Username	Problem	Language	Result	Execution time	Memory
333577		nicholask	Combo (IOI18_combo)	C++14	100 / 100	51 ms	644 KiB

combo

#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
char c[4]={'A','B','X','Y'};
string guess_sequence(int n){
	string ans="";
	for (int i=1; i<=n; i++){
		int fc;
		if (i==1){
			if (press("AB")){;
				if (press("A")){
					ans+='A';
					fc=0;
				} else {
					ans+='B';
					fc=1;
				}
			} else {
				if (press("X")){
					ans+='X';
					fc=2;
				} else {
					ans+='Y';
					fc=3;
				}
			}
			continue;
		}
		if (i==n){
			string q=ans;
			q+=c[(fc+1)%4];
			if (press(q)==n) ans+=c[(fc+1)%4];
			else {
				q.pop_back();
				q+=c[(fc+2)%4];
				if (press(q)==n) ans+=c[(fc+2)%4];
				else ans+=c[(fc+3)%4];
			}
			continue;
		}
		string q="";
		q+=ans;
		q+=c[(fc+1)%4];
		q+=c[(fc+1)%4];
		q+=ans;
		q+=c[(fc+1)%4];
		q+=c[(fc+2)%4];
		q+=ans;
		q+=c[(fc+1)%4];
		q+=c[(fc+3)%4];
		q+=ans;
		q+=c[(fc+2)%4];
		int d=press(q);
		if (d==ans.size()+2) ans+=c[(fc+1)%4];
		else if (d==ans.size()+1) ans+=c[(fc+2)%4];
		else ans+=c[(fc+3)%4];
	}
	return ans;
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:54:8: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   54 |   if (d==ans.size()+2) ans+=c[(fc+1)%4];
      |       ~^~~~~~~~~~~~~~
combo.cpp:55:13: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   55 |   else if (d==ans.size()+1) ans+=c[(fc+2)%4];
      |            ~^~~~~~~~~~~~~~
combo.cpp:35:13: warning: 'fc' may be used uninitialized in this function [-Wmaybe-uninitialized]
   35 |     q+=c[(fc+2)%4];
      |          ~~~^~~

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