Submission #591704

# Submission time Handle Problem Language Result Execution time Memory
591704 2022-07-07T18:51:28 Z tutis Flight to the Ford (BOI22_communication) C++17
88 / 100
3134 ms 2108 KB
#pragma GCC optimize ("O3")
#pragma GCC target("avx,avx2,fma")
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
int prob = 1;
#include "communication.h"
int dec3(int x)//4 bit x
{
	vector<int>ger;
	for (int m = 0; m < 16; m++)
	{
		bool ok = true;
		int v = m;
		while (v != 0)
		{
			if (v % 4 == 3)
				ok = false;
			v /= 2;
		}
		if (ok)
			ger.push_back(m);
	}
	int V[4] = {0, 0, 6, 9};
	for (int i = 1; i <= 3; i++)
	{
		bool ok = true;
		for (int j : ger)
			if (x == (V[i] ^ j))
				ok = false;
		if (ok)
			return i;
	}
	assert(false);
	return 0;
}
int enc3(int X)
{
	int v = 0;
	if (X == 1)
		v = 0;
	else if (X == 2)
		v = 6;
	else if (X == 3)
		v = 9;
	int val = 0;
	for (int t = 0; t < 4; t++)
	{
		val += send(v % 2) << t;
		v /= 2;
	}
	return dec3(val);
}
string S4[4] = {"1000",
                "0001",
                "1110",
                "0111"
               };
int conv4(int i)
{
	int v = 0;
	int p = 1;
	for (char c : S4[i])
	{
		if (c == '1')
			v += p;
		p *= 2;
	}
	return v;
}
bitset<4> dec4(int x)//4 bit x
{
	vector<int>ger;
	for (int m = 0; m < 16; m++)
	{
		bool ok = true;
		int v = m;
		while (v != 0)
		{
			if (v % 4 == 3)
				ok = false;
			v /= 2;
		}
		if (ok)
			ger.push_back(m);
	}
	bitset<4>ret;
	for (int i = 0; i < 4; i++)
	{
		for (int j : ger)
			if (x == (conv4(i) ^ j))
				ret[i] = true;
	}
	return ret;
}
bitset<4> enc4(int X)
{
	int v = conv4(X);
	int val = 0;
	for (int t = 0; t < 4; t++)
	{
		val += (send(v % 2) << t);
		v /= 2;
	}
	auto ret = dec4(val);
	assert(ret[X] == true);
	return ret;
}
const int bitcnt = 29;
int bitcnt1 = 14;
int encB(int v)
{
	int val = 0;
	for (int t = 0; t < bitcnt1; t++)
	{
		val += (send(v % 2) << t);
		v /= 2;
	}
	return val;
}
int C[40][2];
bool prec = false;
int getL(int l)
{
	if (prec == false)
	{
		C[0][0] = 1;
		for (int i = 1; i < 40; i++)
		{
			C[i][0] = C[i - 1][0] + C[i - 1][1];
			C[i][1] = C[i - 1][0];
		}
		prec = true;
	}
	return C[l][0] + C[l][1];
}
int cntT(int m, int l, int g, int x = 0)
{
	if (prec == false)
	{
		C[0][0] = 1;
		for (int i = 1; i < 40; i++)
		{
			C[i][0] = C[i - 1][0] + C[i - 1][1];
			C[i][1] = C[i - 1][0];
		}
		prec = true;
	}
	if (m == (1 << l))
	{
		return C[l][0] + C[l][1];
	}
	int ret = 0;
	for (int b = l; b >= 1; b--)
	{
		int vv = m & (1 << (b - 1));
		int gg = g & (1 << (b - 1));
		m -= vv;
		g -= gg;
		vv /= (1 << (b - 1));
		gg /= (1 << (b - 1));
		int f1 = -1;
		for (int nxt : {0, 1}) {
			int f = gg ^ nxt;
			if (f == 1 && x == 1)
				continue;
			if (nxt < vv)
				ret += C[b][f];
			else if (nxt == vv)
				f1 = f;
		}
		if (f1 == -1)
			break;
		x = f1;
	}
	return ret;
}
int kth(int k, int l, int g, int x = 0)
{
	if (l == 0)
		return 0;
	if (prec == false)
	{
		C[0][0] = 1;
		for (int i = 1; i < 40; i++)
		{
			C[i][0] = C[i - 1][0] + C[i - 1][1];
			C[i][1] = C[i - 1][0];
		}
		prec = true;
	}
	int s = 0;
	for (int b = l; b >= 1; b--)
	{
		int gg = g & (1 << (b - 1));
		g -= gg;
		gg /= (1 << (b - 1));
		for (int nxt : {0, 1})
		{
			int f = gg ^ nxt;
			if (f == 1 && x == 1)
				continue;
			if (k < C[b][f])
			{
				s += ((1 << (b - 1)) * nxt);
				x = f;
				break;
			}
			else
				k -= C[b][f];
		}
	}
	return s;
}
void encode(int N, int X)
{
	if (N < 3)
		return;
	if (N == 3)
	{
		enc3(X);
		return;
	}
	for (int bc = bitcnt; bc >= 5; bc--)
		if (N >= (1 << bc))
		{
			int v = N / (1 << bc);
			int k1 = N % (1 << bc);
			int k0 = (1 << bc) - k1;
			assert(k0 * v + k1 * (v + 1) == N);
			int vv = (X - 1) / v;
			if (vv >= k0)
				vv = k0 + (X - k0 * v - 1) / (v + 1);
			assert(X >= 1 && X <= N);
			assert(vv >= 0 && vv < (1 << bc));

			bitcnt1 = bc;
			int gal1 = encB(vv);
			int c1 = getL(bc);
			int kk0 = cntT(k0, bc, gal1);
			int s = (v + 1) * c1 - kk0;
			int c = cntT(vv, bc, gal1);
			if (X <= k0 * v + v + 1)
			{
				X -= (vv - c) * v;
			}
			else
			{
				X -= vv * (v + 1) - k0;
				X += c * (v + 1) - kk0;
			}
			encode(s, X);
			return;
		}
	if (N >= 4)
	{
		while (N % 4 != 0)
			N++;
		int v = N / 4;
		int vv = (X - 1) / v;
		vv = min(vv, 3);
		bitset<4>gal = enc4(vv);
		int s = 0;
		for (int i = 0; i < 4; i++)
		{
			if (gal[i])
			{
				s += v;
			}
			else if (i < vv)
				X -= v;
		}
		encode(s, X);
		return;
	}
}
pair<int, int> decode(int N)
{
	if (N == 1)
		return {1, 1};
	if (N == 2)
		return {1, 2};
	if (N == 3)
	{
		int val = 0;
		for (int t = 0; t < 4; t++)
			val += receive() << t;
		int v = dec3(val);
		pair<int, int>ans = {1, 2};
		if (v == 1)
			ans.first = 3;
		if (v == 2)
			ans.second = 3;
		return ans;
	}
	for (int bc = bitcnt; bc >= 5; bc--)
		if (N >= (1 << bc))
		{
			int re = 0;
			for (int t = 0; t < bc; t++)
				re += receive() << t;
			int v = N / (1 << bc);
			int k1 = N % (1 << bc);
			int k0 = (1 << bc) - k1;

			int c1 = getL(bc);
			int kk0 = cntT(k0, bc, re);
			int s = (v + 1) * c1 - kk0;

			pair<int, int>r = decode(s);

			auto blo = [&](int p)->int
			{
				int i = (p - 1) / v;
				if (i >= kk0)
					i = kk0 + (p - kk0 * v - 1) / (v + 1);
				return i;
			};
			int i1 = kth(blo(r.first), bc, re);
			int i2 = kth(blo(r.second), bc, re);
			if (i1 <= k0)
				r.first += v * (i1 - cntT(i1, bc, re));
			else
			{
				r.first += (k0 - kk0) * v;
				r.first += (v + 1) * (i1 - cntT(i1, bc, re) - (k0 - kk0));
			}
			if (i2 <= k0)
				r.second += v * (i2 - cntT(i2, bc, re));
			else
			{
				r.second += (k0 - kk0) * v;
				r.second += (v + 1) * (i2 - cntT(i2, bc, re) - (k0 - kk0));
			}
			return r;
		}
	if (N >= 4)
	{
		int N1 = N;
		while (N % 4 != 0)
			N++;
		int re = 0;
		for (int t = 0; t < 4; t++)
			re += receive() << t;
		bitset<4> gal = dec4(re);
		int v = N / 4;
		int s = 0;
		for (int i = 0; i < 4; i++)
			if (gal[i])
				s += v;
		pair<int, int>r = decode(s);
		int sum = 0;
		bool ger1 = false;
		bool ger2 = false;
		for (int i = 0; i < 4; i++)
		{
			if (gal[i])
			{
				if (r.first > sum && r.first <= sum + v && ger1 == false)
				{
					for (int j = 0; j < i; j++)
						if (gal[j] == false)
							r.first += v;
					ger1 = true;
				}
				if (r.second > sum && r.second <= sum + v && ger2 == false)
				{
					for (int j = 0; j < i; j++)
						if (gal[j] == false)
							r.second += v;
					ger2 = true;
				}
				sum += v;
			}
		}
		r.first = min(r.first, N1);
		r.second = min(r.second, N1);
		return r;
	}
	return { -1, -1};
}
// int main()
// {
// 	mt19937 rng(0);
// 	for (int t = 0; t < 1000; t++)
// 	{
// 		int N = 189189;
// 		int val = (rng() % N) + 1;
// 		encode(N, val);
// 		pair<int, int>v = decode(N);
// 		cout << v.first << " " << v.second << endl;
// 		assert(v.first == val || v.second == val);
// 	}
// }
# Verdict Execution time Memory Grader output
1 Correct 11 ms 1708 KB Output is correct
2 Correct 12 ms 1804 KB Output is correct
3 Correct 18 ms 1708 KB Output is correct
4 Correct 13 ms 1808 KB Output is correct
5 Correct 7 ms 1688 KB Output is correct
6 Correct 21 ms 1800 KB Output is correct
7 Correct 59 ms 1668 KB Output is correct
# Verdict Execution time Memory Grader output
1 Partially correct 875 ms 1724 KB Output is partially correct
2 Partially correct 461 ms 1724 KB Output is partially correct
3 Partially correct 561 ms 1744 KB Output is partially correct
4 Partially correct 900 ms 1712 KB Output is partially correct
5 Partially correct 663 ms 1696 KB Output is partially correct
6 Partially correct 400 ms 1752 KB Output is partially correct
7 Partially correct 1993 ms 1768 KB Output is partially correct
8 Partially correct 3134 ms 2108 KB Output is partially correct
9 Partially correct 2752 ms 1868 KB Output is partially correct
10 Partially correct 2622 ms 1812 KB Output is partially correct
11 Partially correct 2768 ms 1796 KB Output is partially correct
12 Partially correct 2776 ms 1796 KB Output is partially correct
13 Partially correct 2750 ms 1876 KB Output is partially correct
14 Partially correct 2784 ms 1968 KB Output is partially correct
15 Partially correct 1358 ms 1848 KB Output is partially correct
16 Partially correct 3125 ms 1760 KB Output is partially correct
17 Partially correct 816 ms 1740 KB Output is partially correct
18 Partially correct 748 ms 1744 KB Output is partially correct
19 Partially correct 744 ms 1804 KB Output is partially correct
20 Partially correct 859 ms 1868 KB Output is partially correct
21 Partially correct 769 ms 1744 KB Output is partially correct
22 Partially correct 797 ms 1796 KB Output is partially correct
23 Partially correct 1279 ms 1876 KB Output is partially correct
24 Correct 8 ms 1740 KB Output is correct
25 Correct 11 ms 1704 KB Output is correct
26 Correct 15 ms 1700 KB Output is correct
27 Correct 9 ms 1756 KB Output is correct
28 Correct 13 ms 1800 KB Output is correct
29 Correct 24 ms 1904 KB Output is correct
30 Correct 48 ms 1620 KB Output is correct