#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
std::string toBinary(int n) {
if (n == 0) return "0";
std::string result;
while (n) {
result += n%2 + 48;
n /= 2;
}
std::reverse(result.begin(), result.end());
return result;
}
int fromBinary(std::string S) {
int result = 0;
int multiple = 1;
for (int i = S.size() - 1; i >= 0; i--) {
if (S[i] - '0') result += multiple;
multiple *= 2;
}
return result;
}
std::vector<bool> send_packet(std::vector<bool> A);
void send_message(std::vector<bool> M, std::vector<bool> C) {
std::vector<int> offsets;
for (int i = 0; i < C.size(); i++) {
if (C[i] == 0) offsets.push_back(i);
send_packet(std::vector<bool>(31, C[i]));
}
std::vector<bool> size_packet(31, 0);
int i_size = 0;
std::string size_string = toBinary(M.size());
for (int i = offsets.size() - 1; i >= 0; i--) {
size_packet[offsets[i]] = size_string[size_string.size() - i_size - 1] - 48;
i_size++;
if (i_size >= size_string.size()) break;
}
send_packet(size_packet);
for (int i = 0; i < M.size();) {
int j = std::min(16, (int)M.size() - i);
std::vector<bool> message(31, 0);
int i_message = 0;
for (int offset : offsets) {
message[offset] = M[i + i_message];
if (++i_message >= j) break;
}
send_packet(message);
i += j;
}
}
std::vector<bool> receive_message(std::vector<std::vector<bool>> R) {
std::vector<int> C;
for (int i = 0; i < 31; i++) {
int count = 0;
for (bool c : R[i]) {
if (c) count++;
else count--;
}
if (count < 0) C.push_back(i);
}
std::string size_string;
for (int offset : C) {
size_string += R[31][offset] + 48;
}
int receiveSize = fromBinary(size_string);
std::vector<bool> result;
int i = 0;
while (i < receiveSize) {
result.push_back(R[i / 16 + 32][C[i % 16]]);
i++;
}
return result;
}
