Submission #487148

#	Time	Username	Problem	Language	Result	Execution time	Memory
487148		stefantaga	Combo (IOI18_combo)	C++14	100 / 100	34 ms	676 KiB

combo

#include "combo.h"

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define all(x) x.begin(),x.end()
#define endl "\n"

string guess_sequence(int n) {
        string ans;
        ans.assign(n, 0);
        char f;
        if (press("AB"))
                if (press("A")) f = 'A';
                else f = 'B';
        else
                if (press("X")) f = 'X';
                else f = 'Y';
        vector<char> r;
        for (char c : "ABXY") if (c and c != f)
                r.push_back(c);
        ans[0] = f;
        if (n == 1) return ans;
        for (int i = 1; i < n-1; i++) {
                string q;
                for (char c : r)
                        q.insert(q.end(), ans.begin(), ans.begin()+i), q.push_back(r[2]), q.push_back(c);
                q.insert(q.end(), ans.begin(), ans.begin()+i), q.push_back(r[1]);
                /*for (char c : q)
                        cout << (int) c << " ";
                cout << endl;*/
                ans[i] = r[press(q)-i];
        }
        ans.pop_back();
        if (press(ans + "A" + ans + "B") == n)
                if (press(ans + "A") == n) f = 'A';
                else f = 'B';
        else
                if (press(ans + "X") == n) f = 'X';
                else f = 'Y';
        ans.push_back(f);
        return ans;
}

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