Submission #635345

#	Time	Username	Problem	Language	Result	Execution time	Memory
635345		marvinthang	Prisoner Challenge (IOI22_prison)	C++17	90 / 100	17 ms	1060 KiB

prison

/*************************************
*    author: marvinthang             *
*    created: 25.08.2022 20:38:19    *
*************************************/

#include <bits/stdc++.h>

using namespace std;

#define                  fi  first
#define                  se  second
#define                 div  ___div
#define                left  ___left
#define               right  ___right
#define                TIME  (1.0 * clock() / CLOCKS_PER_SEC)
#define             MASK(i)  (1LL << (i))
#define             FULL(i)  (MASK(i) - 1)
#define           BIT(x, i)  ((x) >> (i) & 1)
#define  __builtin_popcount  __builtin_popcountll
#define        scan_op(...)  istream & operator >> (istream &in, __VA_ARGS__ &u)
#define       print_op(...)  ostream & operator << (ostream &out, const __VA_ARGS__ &u)
#define          file(name)  if (fopen (name".inp", "r")) { freopen (name".inp", "r", stdin); freopen (name".out", "w", stdout); }

template <class T>             scan_op(vector <T>)  { for (size_t i = 0; i < u.size(); ++i) in >> u[i]; return in; }
template <class T>            print_op(vector <T>)  { out << '{'; for (size_t i = 0; i + 1 < u.size(); ++i) out << u[i] << ", "; if (!u.empty()) out << u.back(); return out << '}'; }
template <class U, class V>   scan_op(pair <U, V>)  { return in >> u.fi >> u.se; }
template <class U, class V>  print_op(pair <U, V>)  { return out << '(' << u.fi << ", " << u.se << ')'; }

const double PI = 3.1415926535897932384626433832795; // acos(-1.0); atan(-1.0);
const int dir[] = {1, 0, -1, 0, 1, 1, -1, -1, 1}; // {2, 1, -2, -1, -2, 1, 2, -1, 2};
const int NUM_BIT = 8;
const int NUM_STATE = 22;
const int p3[] = {1, 3, 9, 27, 81, 243, 729, 2187, 6561};

int get_bit(int n, int bit) { if (bit < 0) return 0; return (n % p3[bit + 1]) / p3[bit]; }

pair <int, int> decode(int code) {
	--code;
	if (code < 0) return make_pair(0, 0);
	return make_pair(NUM_BIT - code / 3 - 1, code % 3);
}

int encode(int bit, int t) {
	if (bit < 0) return 0;
	return (NUM_BIT - bit - 1) * 3 + t + 1;
}

vector <vector <int>> devise_strategy(int n) {
	vector <vector <int>> res(NUM_STATE, vector<int> (n + 1, 0));

	// case 0
	res[0][0] = 0;
	for (int i = 1; i <= n; ++i) 
		res[0][i] = encode(NUM_BIT - 1, get_bit(i, NUM_BIT - 1));

	// case 1 -> 18
	for (int bit = 1; bit < NUM_BIT; ++bit) for (int t = 0; t < 3; ++t) {
		int state = encode(bit, t);
		int cur = bit & 1;
		int pre = cur ^ 1;
		res[state][0] = cur;
		for (int i = 1; i <= n; ++i) {
			int pre_bit = t;
			int cur_bit = get_bit(i, bit);
			if (pre_bit < cur_bit) res[state][i] = -1 - pre;
			else if (pre_bit > cur_bit) res[state][i] = -1 - cur;
			else {
				if (bit > 2) res[state][i] = encode(bit - 1, get_bit(i, bit - 1));
				else {
					int r = i % 9;
					if (r == 0) res[state][i] = -1 - cur;
					else if (r == 8) res[state][i] = -1 - pre;
					else if (r <= 4) res[state][i] = 19;
					else res[state][i] = 20;
				}
			}
		}
	}

	// case 19, 20
	for (int state: {19, 20}) {
		int cur = 1, pre = 0;
		res[state][0] = cur;
		for (int i = 1; i <= n; ++i) {
			int r = i % 9;
			if (state == 19) {
				if (r <= 1) res[state][i] = -1 - cur;
				else if (r >= 4) res[state][i] = -1 - pre;
				else res[state][i] = 21;
			} else {
				if (r <= 5) res[state][i] = -1 - cur;
				else if (r >= 7) res[state][i] = -1 - pre;
				else res[state][i] = 21;
			}
		}
	}

	// case 21
	int cur = 0, pre = 1;
	res[21][0] = cur;
	for (int i = 1; i <= n; ++i) {
		int r = i % 9;
		if (r <= 4) {
			if (r <= 2) res[21][i] = -1 - cur;
			else res[21][i] = -1 - pre;
		} else {
			if (r <= 6) res[21][i] = -1 - cur;
			else res[21][i] = -1 - pre;
		}
	}
	return res;
}

// vector <vector <int>> res;
// int n, a, b;

// void Try(int state) {
// 	if (state < 0) return void(cout << state << '\n');
// 	cout << decode(state) << '\n';
// 	Try(res[state][res[state][0] ? b : a]);
// }

// int main(void) {
// 	ios_base::sync_with_stdio(false); cin.tie(nullptr); // cout.tie(nullptr);
// 	file("ioi22_day1_prison");
// 	// cin >> n >> a >> b;
// 	// for (int i = NUM_BIT; i--; ) cout << get_bit(a, i);
// 	// cout << '\n';
// 	// for (int i = NUM_BIT; i--; ) cout << get_bit(b, i);
// 	// cout << '\n';
// 	// // // cout << bitset<13>(a) << '\n' << bitset<13>(b) << '\n';
// 	// res = devise_strategy(n);
// 	// // // for (int i = 0; i < NUM_STATE; ++i) {
// 	// // // 	cout << decode(i) << ": ";
// 	// // // 	cout << res[i][0] << ' ';
// 	// // // 	for (int j = 1; j <= n; ++j) 
// 	// // // 		if (res[i][j] >= 0) cout << decode(res[i][j]) << ' '; else cout << res[i][j] << ' ';
// 	// // // 	cout << '\n';
// 	// // // }
// 	// Try(0);
// 	cerr << "Time elapsed: " << TIME << " s.\n";
// 	return (0^0);
// }

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 80 / 90