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#include <algorithm>
#include <cassert>
#include <iostream>
#include <random>
#include <utility>
using namespace std;

#include "message.h"
#include "kollib.h"

namespace {
  minstd_rand rng{0x230b0933U};

  constexpr int factor = 10;

  struct Result {
    vector<pair<int, int>> dist;
  };

  void send(int target, Result const& res)
  {
    PutInt(target, res.dist.size());
    for (auto const& p: res.dist) {
      PutInt(target, p.first);
      PutInt(target, p.second);
    }
    Send(target);
  }

  pair<int, Result> receive(int source=-1)
  {
    source = Receive(source);
    Result res;
    res.dist.resize(GetInt(source));
    for (auto& p: res.dist) {
      p.first = GetInt(source);
      p.second = GetInt(source);
    }
    return {source, move(res)};
  }

  int get(int v, int e)
  {
    assert(0 <= e && e < 2);
    if (e == 0) return FirstNeighbor(v+1) - 1;
    else return SecondNeighbor(v+1) - 1;
  }

  Result calculate(vector<int> const& pointsp, vector<int> const& points, int l, int r)
  {
    Result res;
    for (int i = l; i < r; ++i) {
      for (int e = 0; e < 2; ++e) {
        int p = -1;
        int v = pointsp[i];
        int d = 0;
        do {
          int w = get(v, e);
          if (w == p) w = get(v, 1-e);
          p = v;
          v = w;
          ++d;
        } while (!binary_search(points.begin(), points.end(), v));
        res.dist.emplace_back(d, v);
      }
    }
    return res;
  }

  vector<int> combine(int n, vector<pair<int, int>> const& queries, vector<int> const& pointsp, vector<int> const& points, vector<Result> const& results)
  {
    auto find = [&](int v) { return lower_bound(points.begin(), points.end(), v) - points.begin(); };

    auto it = results.begin();
    auto it2 = it->dist.begin();
    int m = points.size();
    vector<pair<int, int>> neigh[2];
    neigh[0].resize(m);
    neigh[1].resize(m);
    for (int i = 0; i < m; ++i) {
      int v = pointsp[i];
      int q = find(v);
      for (int e = 0; e < 2; ++e) {
        while (it2 == it->dist.end()) {
          ++it;
          it2 = it->dist.begin();
        }
        neigh[e][q] = *it2;
        ++it2;
      }
    }
    vector<int> num(points.size());
    int p = -1;
    int v = points[0];
    int d = 0;
    do {
      int q = find(v);
      num[q] = d;
      auto w = neigh[0][q];
      if (w.second == p) w = neigh[1][q];
      d += w.first;
      p = v;
      v = w.second;
    } while (v != points[0]);
    vector<int> answers;
    answers.reserve(queries.size());
    for (auto const& q: queries) {
      int a = find(q.first);
      int b = find(q.second);
      int r = num[a] - num[b];
      if (r < 0) r += n;
      answers.push_back(min(r, n-r));
    }
    return answers;
  }
}

int main()
{
  int const n = NumberOfStudents();
  int const k = NumberOfNodes();
  int const id = MyNodeId();

  int const m = NumberOfQueries();
  if (m == 0) return 0;

  vector<pair<int, int>> queries;
  queries.reserve(m);

  vector<int> points;
  for (int i = 0; i < m; ++i) {
    int a = QueryFrom(i+1) - 1;
    int b = QueryTo(i+1) - 1;
    queries.emplace_back(a, b);
    points.push_back(a);
    points.push_back(b);
  }

  uniform_int_distribution<int> dist(0, n-1);
  for (int i = 0; i < factor*k; ++i) {
    int x = dist(rng);
    points.push_back(x);
  }

  sort(points.begin(), points.end());
  points.erase(unique(points.begin(), points.end()), points.end());
  vector<int> pointsp = points;
  shuffle(pointsp.begin(), pointsp.end(), rng);

  int l = (id + 0LL) * points.size() / k;
  int r = (id + 1LL) * points.size() / k;
  Result result = calculate(pointsp, points, l, r);
  if (id > 0) {
    send(0, move(result));
  } else {
    vector<Result> results;
    results.reserve(k);
    results.push_back(move(result));
    for (int i = 1; i < k; ++i) {
      results.push_back(move(receive(i).second));
    }
    auto res = combine(n, move(queries), move(pointsp), move(points), move(results));
    for (auto ans: res) {
      cout << ans << '\n';
    }
  }

  return 0;
}