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#include "kollib.h"
#include "message.h"
#include <iostream>
#include <set>
#include <map>
#include <vector>
using namespace std;

#define STARTER 0
#define STOPER 1
#define DIR_FIRST 1
#define DIR_SECOND 2
#define IDX_FROM 0
#define IDX_TO 1

typedef enum
{
  READY,
  START,
  SOLUTION,
  STOP
} MSG_TYPE;

void sendREADY(int to);
void receiveREADY(int from);
void sendSTOP(int to);
void sendSTOPAll();
void sendSTART(int to, int begin, int dir);
void receiveSTART(int from);
void sendSOLUTION(int to, int begin, int end, int dist);
void receiveSOLUTION(int from);

set<int> students;

void sendREADY(int to)
{
  PutInt(to, READY);
  Send(to);
}

void receiveREADY(int from)
{
  static set<int>::iterator student = students.begin();
  static int dir = DIR_FIRST;
  if (student != students.end())
  {
    sendSTART(from, *student, dir);
    if (dir == DIR_FIRST)
    { 
      dir = DIR_SECOND;
    }
    else 
    { 
      dir = DIR_FIRST;
      ++student;
    }
  }
}

void sendSTOP(int to)
{
  PutInt(to, STOP);
  Send(to);
}

void sendSTOPAll()
{
  for(int i=0;i<NumberOfNodes();i++)sendSTOP(i);
}

void sendSTART(int to, int begin, int dir)
{
  PutInt(to, START);
  PutInt(to, begin);
  PutInt(to, dir);
  Send(to);
}

void receiveSTART(int from)
{
  int orig_begin = GetInt(from);
  int prev = orig_begin;
  int dir = GetInt(from);
  int begin = dir == DIR_FIRST?FirstNeighbor(prev):SecondNeighbor(prev);
  int dist=1;
  while (students.find(begin)==students.end())
  {
    int n1 = FirstNeighbor(begin);
    int n2 = SecondNeighbor(begin);
    if (n1 != prev)
    {
      prev=begin;
      begin=n1;
    }
    else
    {
      prev=begin;
      begin=n2;
    }
    dist++;
  }
  sendSOLUTION(STOPER,orig_begin,begin,min(dist,NumberOfStudents()-dist));
  sendREADY(from);
}

void sendSOLUTION(int to, int begin, int end, int dist)
{
  PutInt(to, SOLUTION);
  PutInt(to, begin);
  PutInt(to, end);
  PutInt(to, dist);
  Send(to);
}

map<int,map<int,int> > sols;

int get_dist1(int f, int t)
{
      int b=-1;
      int s=0;
      while (f!=t)
      {
        int n1 = sols[f].begin()->first;
        int s1 = sols[f].begin()->second;
        int n2 = (++(sols[f].begin()))->first;
        int s2 = (++(sols[f].begin()))->second;
        if (n1 != b)
        {
          b=f;
          f=n1; 
          s+=s1;
        }
        else
        {
          b=f;
          f=n2;
          s+=s2;
        }
      }
      return min(s,NumberOfStudents()-s);
}

int get_dist2(int f, int t)
{
      int b=-1;
      int s=0;
      while (f!=t)
      {
        int n1 = sols[f].begin()->first;
        int s1 = sols[f].begin()->second;
        int n2 = (++(sols[f].begin()))->first;
        int s2 = (++(sols[f].begin()))->second;
        if (n2!=b)
        {
          b=f;
          f=n2;
          s+=s2;
        }
        else
        {
          b=f;
          f=n1; 
          s+=s1;
        }
      }
      return min(s,NumberOfStudents()-s);
}

void receiveSOLUTION(int from)
{
  int begin = GetInt(from);
  int end = GetInt(from);
  int dist = GetInt(from);
  //cout << "received solution begin:"<<begin<<" end:"<<end<<" dist:"<<dist<<endl;

  sols[begin][end]=dist;
  sols[end][begin]=dist;

  static int i=0;
  i++;
  //printf("solution nr%d\n",i);
  if(i==students.size()*2)
  {
/*
    for(map<int,map<int,int> >::iterator it = sols.begin();it!=sols.end();++it)
    {
      printf("sols %d: [%d,%d,%d,%d]\n",it->first,it->second.begin()->first,it->second.begin()->second,(++(it->second.begin()))->first,(++(it->second.begin()))->second);
    }
*/
    int q=1;
    while (q<=NumberOfQueries())
    {
      int f = QueryFrom(q);
      int t = QueryTo(q);
      int s1 = get_dist1(f,t);
      int s2 = get_dist2(f,t);
      printf("%d\n",min(s1,s2));
      q++;
    }
    sendSTOPAll();
  }
}

int receive()
{
  int from = Receive(-1);
  MSG_TYPE msg_type = (MSG_TYPE)GetInt(from);
  switch(msg_type)
  {
    case READY:
      receiveREADY(from);
      break;
    case START:
      receiveSTART(from);
      break;
    case SOLUTION:
      receiveSOLUTION(from);
      break;
    case STOP:
      return -1;
      break;
  }
  return 0;
}

void init()
{
  for (int i=0;i<NumberOfQueries();i++)
  {
    students.insert(QueryFrom(i+1));
    students.insert(QueryTo(i+1));
  }
  for (int i=0;i<NumberOfNodes()*2;i++)
  {
    int r = (abs(i*(i+100007)+9432898523))%NumberOfStudents() + 1;
    students.insert(r);
  }
}

void start()
{
  while (1)
  {
    if(receive()<0)return;
  }
}

void work()
{
  sendREADY(STARTER);
  while (1)
  {
    if(receive()<0)return;
  }
}


void stop()
{
  while (1)
  {
    if(receive()<0)return;
  }
}

int main()
{
  if(NumberOfQueries()==0) return 0;
  init();
  if (MyNodeId() == STARTER) start();
  else if (MyNodeId() == STOPER) stop();
  else work();
  return 0;
}