Submission #270602

#	Time	Username	Problem	Language	Result	Execution time	Memory
270602		nafis_shifat	Combo (IOI18_combo)	C++14	100 / 100	42 ms	648 KiB

combo

#include "combo.h"
#include<bits/stdc++.h>
using namespace std;
string guess_sequence(int N) {
	if(N==1) {
		int k=press("A");
		if(k==1) return "A";
		k=press("B");
		if(k==1) return "B";
		k=press("X");
		if(k==1) return "X";
		return "Y";
	}


	int k=press("ABA");
	char c;
	if(k==0) {
		if(press("X")) c='X';
		else c='Y';
	} else {
		if(press("A")) c='A';
		else c='B';
	}


	string res="";
	res+=c;

	char a[3]={'A','B','X'};
	if(c=='A')a[0]='Y';
	if(c=='B')a[1]='Y';
	if(c=='X')a[2]='Y';


	for(int i=2;i<N;i++) {
		int z=res.size()+1;
		string tmp=res+a[0]+a[1]+res+a[0]+a[0]+res+a[0]+a[2]+res+a[1];

		int r=press(tmp);

		if(r==z)res+=a[1];
		else if(r>z)res+=a[0];
		else res+=a[2];
	}

	if(press(res+a[0])==N)res+=a[0];
	else if(press(res+a[1])==N)res+=a[1];
	else res+=a[2];
	return res;
}

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