Submission #778677

#	Time	Username	Problem	Language	Result	Execution time	Memory
778677		Silence	Combo (IOI18_combo)	C++17	100 / 100	31 ms	612 KiB

combo

#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
std::string guess_sequence(int N) {
	string s;
	string ans;
	auto third_subtask = [&](int n){
		string cur = "ABXY";
		string s;
		string ans;
		ans+=cur[0];
		ans+=cur[1];
		if (press(ans) > 0){
			ans.pop_back();
			if (press(ans) == 1){
				for (int j = 0;j<4;++j){
					if (j != 0){
						s+=cur[j];
					}
				}
			}
			else{
				ans.pop_back();
				ans+=cur[1];
				for (int j = 0;j<4;++j){
					if (j != 1){
						s+=cur[j];
					}
				}
			}	
		}
		else{
			ans.pop_back();
			ans.pop_back();
			ans+=cur[2];
			if (press(ans) == 1){
				for (int j = 0;j<4;++j){
					if (j != 2){
						s+=cur[j];
					}
				}
			}
			else{
				ans.pop_back();
				ans+=cur[3];
				for (int j = 0;j<4;++j){
					if (j != 3){
						s+=cur[j];	
					}
				}
			}	
		}
		if (n == 1)return ans;
		//n + 1 + n + 2
		for (int i = 0;i<n - 2;++i){
			string p = ans;
			p+=s[0];
			for (int j = 0;j<3;++j){
				string t = ans;
				t+=s[1];
				t+=s[j];
				p+=t;        
			}
			int v = press(p);
			if (v == i + 2){
				ans+=s[0];
			}	
			else if (v == i + 1){
				ans+=s[2];
			}
			else{
				ans+=s[1];
			}
		}
		for (int i = 0;i<2;++i){
			ans+=s[i];
			if (press(ans) == n){
				return ans;
			}
			ans.pop_back();
		}
		ans+=s[2];
		return ans;	
	};
	string v = third_subtask(N);
	//cout<<v<<'\n';
	return v;  
}

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