#include "communication.h"
#include <iostream>
#include <cstdio>
#include <vector>
using namespace std;
// <|°_°|>
// M. Broccoli
struct segments_set {
vector <pair <int, int>> Segments;
void push_back(pair <int, int> a) {
Segments.push_back(a);
return;
}
int sum() {
int ans = 0;
for (pair <int, int> a : Segments)
ans += a.second - a.first;
return ans;
}
pair <segments_set, segments_set> split(int up) {
int cut = (sum() + up) / 2;
int cur = 0;
pair <segments_set, segments_set> ans;
int fill = 0;
for (pair <int, int> a : Segments)
{
if (!fill && cur + a.second - a.first > cut)
{
if (cur == cut)
ans.second.push_back(a);
else
{
int opt = a.first + cut - cur;
ans.first.push_back({a.first, opt});
ans.second.push_back({opt, a.second});
}
fill = 1;
}
else
{
if (fill)
ans.second.push_back(a);
else
ans.first.push_back(a);
}
cur += a.second - a.first;
}
return ans;
}
bool contain(int target) {
for (pair <int, int> a : Segments)
{
if (a.first <= target && target < a.second)
return true;
}
return false;
}
void merge(segments_set s) {
for (pair <int, int> a : s.Segments)
Segments.push_back(a);
return;
}
};
pair <int, int> DecodeStep() {
vector <int> Poss(4);
vector <int> Bits(4);
Poss[0] = Poss[1] = 1;
Poss[2] = Poss[3] = 0;
for (int i = 0; i < 4; i ++)
{
Bits[i] = receive();
if (i && Bits[i] == Bits[i - 1])
{
Poss[Bits[i] ^ 1] --;
if (i == 2)
{
Poss[2 ^ Bits[i]] ++;
Poss[3 ^ Bits[i]] -= 42;
}
else
Poss[3 ^ Bits[i]] ++;
}
}
vector <int> ans;
for (int i = 0; i < 4; i ++)
{
if (Poss[i] > 0)
ans.push_back(i);
}
if (ans.size() == 1)
return {ans[0], ans[0]};
return {ans[0], ans[1]};
}
void EncodeStep(int a) {
vector <int> ToSend(4, 0);
if (a == 0)
ToSend = {0, 0, 0, 0};
if (a == 1)
ToSend = {1, 1, 1, 1};
if (a == 2)
ToSend = {1, 0, 0, 1};
if (a == 3)
ToSend = {0, 1, 1, 0};
for (int i = 0; i < 4; i ++)
{
send(ToSend[i]);
}
return;
}
void encode(int nbMessages, int message) {
segments_set correct;
segments_set incorrect;
correct.push_back({1, nbMessages});
while (correct.sum() + incorrect.sum() > 4)
{
pair <segments_set, segments_set> nvCorr = correct.split(1);
pair <segments_set, segments_set> nvIncorr = incorrect.split(0);
int x;
if (nvCorr.first.contain(message) || nvIncorr.first.contain(message))
x = send(1);
else
x = send(0);
if (x == 1)
{
correct = nvCorr.first;
correct.merge(nvIncorr.first);
incorrect = nvCorr.second;
}
else
{
correct = nvCorr.second;
correct.merge(nvIncorr.second);
incorrect = nvCorr.first;
}
}
vector <int> poss;
for (pair <int, int> a : correct.Segments)
{
for (int i = a.first; i < a.second; i ++)
poss.push_back(i);
}
for (pair <int, int> a : incorrect.Segments)
{
for (int i = a.first; i < a.second; i ++)
poss.push_back(i);
}
for (int i = 0; i < (int)poss.size(); i ++)
{
if (message == poss[i])
EncodeStep(i);
}
return;
}
pair <int, int> decode(int nbMessages) {
segments_set correct;
segments_set incorrect;
correct.push_back({1, nbMessages});
while (correct.sum() + incorrect.sum() > 4)
{
pair <segments_set, segments_set> nvCorr = correct.split(1);
pair <segments_set, segments_set> nvIncorr = incorrect.split(0);
if (receive() == 1)
{
correct = nvCorr.first;
correct.merge(nvIncorr.first);
incorrect = nvCorr.second;
}
else
{
correct = nvCorr.second;
correct.merge(nvIncorr.second);
incorrect = nvCorr.first;
}
}
vector <int> poss;
for (pair <int, int> a : correct.Segments)
{
for (int i = a.first; i < a.second; i ++)
poss.push_back(i);
}
for (pair <int, int> a : incorrect.Segments)
{
for (int i = a.first; i < a.second; i ++)
poss.push_back(i);
}
pair <int, int> x = DecodeStep();
return {poss[min(x.first, (int)poss.size() - 1)], poss[min(x.second, (int)poss.size() - 1)]};
}
