Submission #92801

#	Time	Username	Problem	Language	Result	Execution time	Memory
92801		psmao	Combo (IOI18_combo)	C++14	100 / 100	60 ms	632 KiB

combo

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

#define fo(i,s,t) for(int i = s; i <= t; ++ i)
#define fd(i,s,t) for(int i = s; i >= t; -- i)
#define bf(i,s) for(int i = head[s]; i; i = e[i].next)
#define mp make_pair
#define fi first
#define se second
#define pii pair<int,int>
#define pb push_back
#define VI vector<int>
#define sf scanf
#define pf printf
#define fp freopen
#define SZ(x) ((int)(x).size())
#ifdef MPS
#define D(x...) printf(x)
#else
#define D(x...)
#endif
typedef long long ll;
typedef double db;
typedef unsigned long long ull;
const int inf = 1<<30;
const ll INF = 1ll<<60;
const db Inf = 1e20;
const db eps = 1e-9;

string convert(int x)
{
	if(x == 1) return "A";
	else if(x == 2) return "B";
	else if(x == 3) return "X";
	else return "Y";
}
int candi[4];
string guess_sequence(int n)
{
	int first;
	string ret = "";
	if(press("AB"))
	{
		if(press("A")) first = 1, ret = "A";
		else first = 2, ret = "B";
	}
	else 
	{
		if(press("X")) first = 3, ret = "X";
		else first = 4, ret = "Y"; 
	}
	srand(time(NULL));
	fo(i,1,4) if(i != first) candi[i] = i;
	fo(i,2,n-1) 
	{
		random_shuffle(candi+1,candi+3+1);
		fo(a,1,3)
		{
			fo(b,1,3) if(a != b)
			{
				string tmp = ret + convert(candi[a]);
				fo(c,1,3)
					tmp = tmp + ret + convert(candi[b]) + convert(candi[c]);
				int answer = press(tmp);
				if(answer == i + 1) ret = ret + convert(candi[b]);
				else if(answer == i) ret = ret + convert(candi[a]);
				else fo(k,1,3) if(k != a && k != b) {ret = ret + convert(candi[k]); break;}
				goto loop;
			}
		}
		loop:;
	}
	if(n != 1)
	{
		random_shuffle(candi+1,candi+3+1);
		string tmp = ret + convert(candi[1]) + ret + convert(candi[2]);
		if(press(tmp) == n) 
		{
			tmp = ret + convert(candi[1]);
			if(press(tmp) == n) {ret = tmp; goto gg;}
			ret = ret + convert(candi[2]); goto gg;
		}
		ret = ret + convert(candi[3]);
		gg:;
	}
	return ret;
}

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