Submission #108122

#	Time	Username	Problem	Language	Result	Execution time	Memory
108122		autumn_eel	Combo (IOI18_combo)	C++14	5 / 100	2 ms	276 KiB

combo

#include <bits/stdc++.h>
#define rep(i,n)for(int i=0;i<(n);i++)
using namespace std;

#include "combo.h"

string s="ABXY";

string guess_sequence(int N) {
	char c='?';
	rep(i,3){
		string ask;ask+=s[i];
		int res=press(ask);
		if(res){
			c=s[i];
			break;
		}
	}
	if(c=='?')c=s[3];
	string ans;ans+=c;
	string t;
	rep(i,4){
		if(s[i]!=c)t+=s[i];
	}
	for(int i=1;i<N-1;i++){
		string ask=ans+t[0];
		rep(j,3)ask+=ans+t[1]+t[j];
		int res=press(ask);
		if(res==i){
			ans+=t[2];
		}
		else if(res==i+1){
			ans+=t[0];
		}
		else if(res==i+2){
			ans+=t[1];
		}
		else abort();
	}
	char last='?';
	rep(i,2){
		int res=press(ans+t[i]);
		if(res==N){
			last=t[i];
			break;
		}
	}
	if(last=='?')last=t[2];
	ans+=last;
	return ans;
}

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