Submission #555797

#	Time	Username	Problem	Language	Result	Execution time	Memory
555797		inventiontime	Combo (IOI18_combo)	C++17	100 / 100	32 ms	560 KiB

combo

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

#define int ll
#define endl '\n' //comment for interactive

#define fast_io ios::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define pb push_back
#define re resize
#define ff first
#define ss second
#define all(x) (x).begin(), (x).end()
#define loop(i, n) for(int i = 0; i < n; i++)
#define loop1(i, n) for(int i = 1; i <= n; i++)
#define print(x) cout << #x << ": " << x << endl << flush

typedef long long ll;
typedef vector<int> vi;
typedef array<int, 2> ii;
typedef array<int, 3> ti;
typedef vector<ii> vii;
typedef vector  <ti> vti;
typedef priority_queue<int> pq;

template<class T> bool ckmin(T&a, T b) { bool B = a > b; a = min(a, b); return B; }
template<class T> bool ckmax(T&a, T b) { bool B = a < b; a = max(a, b); return B; }

const int inf = 1e17;
//const int maxn = ;

string guess_sequence(signed N) {

    char init = ' ';
    if(press("AB") >= 1) {
        if(press("A") >= 1) init = 'A';
        else init = 'B';
    } else {
        if(press("X") >= 1) init = 'X';
        else init = 'Y';
    }

    if(N == 1) return {init};

    char d[4] = {'A', 'B', 'X', 'Y'};
    vector<char> c;
    loop(i, 4) if(d[i] != init) c.pb(d[i]);
    string res = {init};
    loop1(i, N-2) {
        int x = press(
            res + c[0] + 
            res + c[1] + c[0] +
            res + c[1] + c[1] +
            res + c[1] + c[2]
        );
        if(x == i)
            res += c[2];
        else if(x == i+1)
            res += c[0];
        else
            res += c[1];
    }

    if(press(res + c[0]) == N) res += c[0];
    else if(press(res + c[1]) == N) res += c[1];
    else res += c[2];

    return res;

}

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