| # | 제출 시각 | 아이디 | 문제 | 언어 | 결과 | 실행 시간 | 메모리 |
|---|---|---|---|---|---|---|---|
| 1194809 | tutis | Message (IOI24_message) | C++20 | 0 ms | 0 KiB |
#pragma GCC target("avx2")
#pragma GCC optimization("O3")
#pragma GCC optimization("unroll-loops")
#include "message.h"
#include <algorithm>
#include <chrono>
#include <iostream>
#include <random>
#include <bitset>
#include <vector>
#include <assert.h>
#include <math.h>
using namespace std;
int counter = 0;
bool initialized = false;
const int bitsCnt = 16;
bitset<31> seqs[1 << bitsCnt];
bitset<31> masks[110];
const int64_t seed1 = 123125173141312563;
const int64_t seed2 = 981891681523456374;
bitset<31> globC;
mt19937_64 rng(0);
void init()
{
counter = 0;
if (!initialized)
{
mt19937_64 rng(seed1);
initialized = true;
for (int i = 0; i < (1 < bitsCnt); i++)
{
seqs[i] = i;
}
for (int i = 0; i < (1 << bitsCnt); i++)
{
for (int j = bitsCnt; j < 31; j++)
{
seqs[i][j] = seqs[i][j - bitsCnt];
}
}
shuffle(seqs, seqs + (1 << bitsCnt), rng);
for (int i = 0; i < 110; i++)
{
for (int j = 0; j < 31; j++)
{
masks[i] = rng();
}
}
}
}
bitset<31> send(bitset<31> A)
{
if (counter > 100)
{
assert(false);
}
A = A ^ masks[counter];
vector<bool> Avector(31);
for (int i = 0; i < 31; i++)
{
Avector[i] = A[i];
}
vector<bool> recVector = send_packet(Avector);
bitset<31> received;
for (int j = 0; j < 31; j++)
{
received[j] = recVector[j];
}
received = received ^ masks[counter];
counter++;
return received;
}
struct X
{
bitset<31> C;
};
bool subset(bitset<31> a, bitset<31> b)
{
return (a & b) == a;
}
X decode(X x, bitset<31> msg, bitset<31> bits)
{
int i = (1 << bitsCnt) - 1;
vector<int> options;
for (bitset<31> sub = bits; i >= 0; sub = bits & bitset<31>(sub.to_ullong() - 1))
{
bitset<31> diff = msg ^ seqs[i];
diff |= x.C;
if (diff.count() > 15)
{
i--;
continue;
}
if (!subset(bits & diff, sub))
{
i--;
continue;
}
options.push_back(i);
i--;
}
if (options.size() == 0)
{
exit(2);
}
bitset<31> diff;
diff.flip();
for (int i : options)
{
diff &= msg ^ seqs[i];
}
x.C |= diff;
return x;
}
bitset<31> get_bits(int step, bitset<31> xC)
{
mt19937_64 rng(step);
bitset<31> ret;
while (ret.count() > bitsCnt)
{
ret[rng() % 31] = false;
}
while (ret.count() < bitsCnt)
{
int i = rng() % 31;
ret[i] = true;
}
return ret;
}
void send_message(vector<bool> M, vector<bool> Cvect)
{
rng = mt19937_64(seed2);
bitset<31> C;
for (int i = 0; i < 31; i++)
{
C[i] = Cvect[i];
}
globC = C;
init();
X x;
int step = 0;
while (x.C.count() < 15)
{
bitset<31> bits = get_bits(step, x.C);
int val = 0;
int cnt = 0;
for (int i = 0; i < 31; i++)
{
if (bits[i])
{
if (C[i])
{
val += 1 << cnt;
}
cnt++;
}
}
bitset<31> to_send = seqs[val % (1 << bitsCnt)];
for (int i = 0; i < 31; i++)
{
if (C[i])
{
to_send[i] = rng() % 2;
}
}
bitset<31> received = send(to_send);
x = decode(x, received, bits);
step++;
if (counter >= 100)
{
assert(false);
}
}
bitset<31> good = x.C.flip();
int offset = (1024 - M.size()) % 16;
vector<bool> X;
for (int i = 0; i < offset; i++)
{
X.push_back(1);
}
X.push_back(0);
for (int v : M)
{
X.push_back(v);
}
int i = 0;
while (i < X.size())
{
bitset<31> packet;
for (int v = 0; v < 31; v++)
{
if (good[v])
{
if (i < X.size())
{
packet[v] = X[i];
i++;
}
}
}
send(packet);
}
}
std::vector<bool> receive_message(vector<vector<bool>> Rvect)
{
rng = mt19937_64(seed2);
vector<bitset<31>> R(Rvect.size());
for (int i = 0; i < Rvect.size(); i++)
{
bitset<31> b;
for (int j = 0; j < 31; j++)
{
b[j] = Rvect[i][j];
}
R[i] = b;
}
init();
for (int i = 0; i < R.size(); i++)
{
R[i] = R[i] ^ masks[i];
}
X x;
int i = 0;
int step = 0;
while (x.C.count() < 15 && i < R.size())
{
x = decode(x, R[i], get_bits(step, x.C));
i++;
step++;
}
bitset<31> good = x.C.flip();
vector<int> X;
for (; i < R.size(); i++)
{
for (int v = 0; v < 31; v++)
{
if (good[v])
{
X.push_back(R[i][v]);
}
}
}
int offset = 0;
while (offset < X.size() && X[offset])
{
offset++;
}
vector<bool> answer;
for (int i = offset + 1; i < X.size(); i++)
{
answer.push_back(X[i]);
}
while ((1024 - answer.size()) % 16 != offset && answer.size() > 0)
{
answer.pop_back();
}
return answer;
}
vector<vector<bool>> sent;
int main()
{
for (int i = 0; i < 100; i++)
{
vector<bool> msg(1024);
for (int i = 0; i < msg.size(); i++)
{
msg[i] = rng() % 2;
}
send_message(msg,
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1});
vector<bool> received = receive_message(sent);
cout << "Q = " << sent.size() << endl;
if (msg != received)
{
cout << "mismatch!" << endl;
}
else
{
cout << "ok" << endl;
}
}
}
vector<bool> send_packet(std::vector<bool> A)
{
for (int i = 0; i < 31; i++)
{
if (globC[i])
{
A[i] = rng() % 2;
}
}
sent.push_back(A);
return A;
}