Submission #1000800

#	Time	Username	Problem	Language	Result	Execution time	Memory
1000800		c2zi6	Combo (IOI18_combo)	C++14	100 / 100	24 ms	1844 KiB

combo

#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
#define ff first
#define ss second
#define pb push_back
#define all(a) (a).begin(), (a).end()
#define replr(i, a, b) for (int i = int(a); i <= int(b); ++i)
#define reprl(i, a, b) for (int i = int(a); i >= int(b); --i)
#define rep(i, n) for (int i = 0; i < int(n); ++i)
#define mkp(a, b) make_pair(a, b)
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> PII;
typedef vector<int> VI;
typedef vector<PII> VPI;
typedef vector<VI> VVI;
typedef vector<VVI> VVVI;
typedef vector<VPI> VVPI;
typedef pair<ll, ll> PLL;
typedef vector<ll> VL;
typedef vector<PLL> VPL;
typedef vector<VL> VVL;
typedef vector<VVL> VVVL;
typedef vector<VPL> VVPL;
template<class T> T setmax(T& a, T b) {if (a < b) return a = b; return a;}
template<class T> T setmin(T& a, T b) {if (a < b) return a; return a = b;}
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
template<class T>
using indset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#include "combo.h"

string guess_sequence(int n) {
    string s;
    if (press("AB")) {
        if (press("A")) s.pb('A');
        else s.pb('B');
    } else {
        if (press("X")) s.pb('X');
        else s.pb('Y');
    }
    if (n == 1) return s;
    string ret = s;
    if ('A' != s[0]) s.pb('A');
    if ('B' != s[0]) s.pb('B');
    if ('X' != s[0]) s.pb('X');
    if ('Y' != s[0]) s.pb('Y');
    rep(i, n-2) {
        string qr;
        qr += ret;
        qr.pb(s[1]);
        qr += ret;
        qr.pb(s[2]);
        qr.pb(s[1]);
        qr += ret;
        qr.pb(s[2]);
        qr.pb(s[2]);
        qr += ret;
        qr.pb(s[2]);
        qr.pb(s[3]);
        int cnt = press(qr)-ret.size();
        if (cnt == 0) ret.pb(s[3]);
        else if (cnt == 1) ret.pb(s[1]);
        else if (cnt == 2) ret.pb(s[2]);
        /*cout << "CURRENT GUESS: " << ret << endl;*/
    }
    ret.pb(s[1]);
    if (press(ret) == n) return ret;
    ret.pop_back();
    ret.pb(s[2]);
    if (press(ret) == n) return ret;
    ret.pop_back();
    ret.pb(s[3]);
    return ret;
}

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