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#include <cstdio>
#include <cstdlib>
#include <string>
#include <vector>
#include <algorithm>
#include <map>
#include <set>
#include <queue>
#include <time.h>
#include "message.h"
#include "kollib.h"
using namespace std;

struct special_dude {
  int idx_;
  int offset_;
  int dir_;
  special_dude() : idx_(0), offset_(0), dir_(0) {}
  special_dude(int idx, int offset, int dir) : idx_(idx), offset_(offset), dir_(dir) {}
};

struct task_results {
  int id1_, id2_;
  int len1_, len2_;
  vector<special_dude> dudes;
};

set<int> is_in_query;
vector<pair<int, int> > queries;

int main() {
  // Read all queries.
  for (int i = 1; i <= NumberOfQueries(); i++) {
    int from = QueryFrom(i);
    int to = QueryTo(i);
    is_in_query.insert(from);
    is_in_query.insert(to);
    queries.push_back(make_pair(from, to));
  }

  // Handle special case for n < nodes - 1.
  if (NumberOfStudents() < NumberOfNodes() - 1) {
    if (MyNodeId() != 0) {
      return 0;
    }

    map<int, int> offsets;
    int curr = 1;
    int prev = -1;

    for (int i = 0; ; i++) {
      int next = FirstNeighbor(curr);
      if (next == prev) {
        next = SecondNeighbor(curr);
      }

      offsets[curr] = i;
      prev = curr;
      curr = next;

      if (curr == 1) {
        break;
      }
    }

    for (int i = 0; i < queries.size(); i++) {
      int a = queries[i].first;
      int b = queries[i].second;
      //printf("a: %d, b: %d\n", a, b);
      printf("%d\n", min(abs(offsets[a] - offsets[b]), NumberOfStudents() - abs(offsets[a] - offsets[b])));
    }
    return 0;
  }

  // Normal processing: master.
  if (MyNodeId() == 0) {
    srand(time(NULL));
  
    // Randomly choose starting points for all tasks.
    map<int, bool> already_chosen;
    vector<int> start_ids;
    start_ids.push_back(-1);
    for (int i = 0; i < NumberOfNodes() - 1; i++) {
      int random_idx;

      do {
        random_idx = 1 + (rand() % NumberOfStudents());
      } while (already_chosen.find(random_idx) != already_chosen.end());

      start_ids.push_back(random_idx);
      already_chosen[random_idx] = true;
    }

    // Send information about all starting points to all tasks.
    for (int i = 1; i < NumberOfNodes(); i++) {
      for (int j = 1; j < NumberOfNodes(); j++) {
        PutInt(i, start_ids[j]);
      }
      Send(i);
    }

    // Wait for all the tasks to respond with their results.
    map<int, task_results> results;
    for (int i = 0; i < NumberOfNodes() - 1; i++) {
      int task = Receive(-1);

      task_results tr;
      tr.id1_ = GetInt(task);
      tr.len1_ = GetInt(task);
      tr.id2_ = GetInt(task);
      tr.len2_ = GetInt(task);

      //printf("task %d responded: it hit %d (len %d) and %d (len %d) (started from %d)\n", task, tr.id1_, tr.len1_, tr.id2_, tr.len2_, start_ids[task]);

      int targets_found = GetInt(task);
      for (int j = 0; j < targets_found; j++) {
        special_dude dd;
        dd.idx_ = GetInt(task);
        dd.offset_ = GetInt(task);
        dd.dir_ = GetInt(task);

        tr.dudes.push_back(dd);

        //printf("requested dude %d at offset %d in direction %d\n", dd.idx_, dd.offset_, dd.dir_);
      }

      results[task] = tr;
    }

    // Calculate offsets for all requested dudes.
    map<int, int> offsets;
    int curr = 1;
    int prev = -1;
    int base_offset = 0;
    int curr_dir = 0;
    do {
      int next = results[curr].id1_;
      curr_dir = 0;
      if (next == prev) {
        next = results[curr].id2_;
        curr_dir = 1;
      }

      //printf("curr: %d, base offset: %d, curr dir: %d\n", curr, base_offset, curr_dir);

      for (int i = 0; i < results[curr].dudes.size(); i++) {
        if (results[curr].dudes[i].dir_ == curr_dir) {
          offsets[results[curr].dudes[i].idx_] = base_offset + results[curr].dudes[i].offset_;
          //printf("assigning %d the index %d, as the sum of %d and %d\n",
          //       results[curr].dudes[i].idx_, offsets[results[curr].dudes[i].idx_],
          //       base_offset, results[curr].dudes[i].offset_);
        }
      }

      prev = curr;
      curr = next;

      if (results[curr].id1_ == prev) {
        base_offset += results[curr].len1_ + 1;
      } else {
        base_offset += results[curr].len2_ + 1;
      }
    } while (start_ids[curr] != start_ids[1]);
    
    for (int i = 0; i < queries.size(); i++) {
      int a = queries[i].first;
      int b = queries[i].second;
      printf("%d\n", min(abs(offsets[a] - offsets[b]), NumberOfStudents() - abs(offsets[a] - offsets[b])));
    }
    //for (map<int, int>::iterator it = offsets.begin(); it != offsets.end(); it++) {
    //  printf("offset[%d] = %d\n", it->first, it->second);
    //}
  } else /* Normal processing: tasks */ {
    // Receive information about all start ids from the master.
    int my_start_id;
    map<int, int> start_ids;
    int i;

    Receive(0);
    for (i = 1; i <= NumberOfNodes() - 1; i++) {
      int id = GetInt(0);
      start_ids[id] = i;
      
      if (i == MyNodeId()) {
        my_start_id = id;
      }
    }

    //printf("[%d] received, my start id: %d\n", MyNodeId(), my_start_id); fflush(stdout);

    // Get the two of initial neighbours.
    int first = FirstNeighbor(my_start_id);
    int second = SecondNeighbor(my_start_id);

    // Explore the first neighbour until another starting point is found.
    vector<special_dude> special_dudes;
    int curr = first;
    int prev = my_start_id;
    int end_ids[2], end_tasks[2], end_lens[2];

    if (is_in_query.find(my_start_id) != is_in_query.end()) {
      special_dudes.push_back(special_dude(my_start_id, 0, 0));
      special_dudes.push_back(special_dude(my_start_id, 0, 1));
    }

    for (i = 1; start_ids.find(curr) == start_ids.end(); i++) {
      //printf("[%d] first curr: %d\n", MyNodeId(), curr); fflush(stdout);

      int next = FirstNeighbor(curr);
      if (next == prev) {
        next = SecondNeighbor(curr);
      }

      if (is_in_query.find(curr) != is_in_query.end()) {
        special_dudes.push_back(special_dude(curr, i, 0));
      }

      prev = curr;
      curr = next;
    }
    end_ids[0] = curr;
    end_tasks[0] = start_ids[curr];
    end_lens[0] = i - 1;

    // Explore the second neighbour until another starting point is found.
    curr = second;
    prev = my_start_id;

    for (i = 1; start_ids.find(curr) == start_ids.end(); i++) {
      //printf("[%d] second curr: %d\n", MyNodeId(), curr); fflush(stdout);

      int next = FirstNeighbor(curr);
      if (next == prev) {
        next = SecondNeighbor(curr);
      }

      if (is_in_query.find(curr) != is_in_query.end()) {
        special_dudes.push_back(special_dude(curr, i, 1));
      }

      prev = curr;
      curr = next;
    }
    end_ids[1] = curr;
    end_tasks[1] = start_ids[curr];
    end_lens[1] = i - 1;

    //printf("[%d] done, sending...\n", MyNodeId()); fflush(stdout);

    // Send information to the master.
    PutInt(0, end_tasks[0]);
    PutInt(0, end_lens[0]);
    PutInt(0, end_tasks[1]);
    PutInt(0, end_lens[1]);

    PutInt(0, special_dudes.size());
    for (i = 0; i < special_dudes.size(); i++) {
      PutInt(0, special_dudes[i].idx_);
      PutInt(0, special_dudes[i].offset_);
      PutInt(0, special_dudes[i].dir_);
    }
    Send(0);

    //printf("[%d] sent.\n", MyNodeId()); fflush(stdout);
  }

  return 0;
}