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#include <algorithm>
#include <cstdio>
#include <cstdlib>
#include <map>
#include <set>
#include <vector>

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

using namespace std;

const int kMaxStartPoints = 500;

class Edge {
 public:
  Edge(const int from_, const int to_, const int offset_) : from(from_), to(to_), offset(offset_) {}

  int from;
  int to;
  int offset;
};

class Query {
 public:
  Query(const int cursor_, const int student_, const int offset_) : cursor(cursor_), student(student_), offset(offset_) {}

  int cursor;
  int student;
  int offset;
};

void ChooseCursors(const int l, const int r, int points, vector<pair<int, int> > *cursors) {
  if (points == 0) return;
  if (l == r) {
    cursors->push_back(make_pair(l, FirstNeighbor(l)));
    cursors->push_back(make_pair(l, SecondNeighbor(l)));
    return;
  }
  const int m = (l + r) / 2;
  int all = r - l + 1;
  int left = m - l + 1;
  int points_left = 0;
  int points_right = 0;
  while (points--) if (rand() % all-- < left) {
    ++points_left;
    --left;
  } else {
    ++points_right;
  }
  ChooseCursors(l, m, points_left, cursors);
  ChooseCursors(m + 1, r, points_right, cursors);
}

int n;

void BuildCursors(vector<pair<int, int> > *cursors) {
  ChooseCursors(1, n, min(n, kMaxStartPoints), cursors);
  sort(cursors->begin(), cursors->end());
}

int Negate(const int i) {
  return (n - i) % n;
}

int Add(const int i, const int j) {
  return (i + j) % n;
}

void DFS(const int a, const int offset, const vector<vector<pair<int, int> > > &all_edges, const vector<vector<pair<int, int> > > &all_queries, vector<bool> *visited, map<int, int> *query_offsets) {
  if ((*visited)[a]) return;
  (*visited)[a] = true;
  for (int i = 0; i < all_edges[a].size(); ++i) DFS(all_edges[a][i].first, Add(offset, all_edges[a][i].second), all_edges, all_queries, visited, query_offsets);
  for (int i = 0; i < all_queries[a].size(); ++i) (*query_offsets)[all_queries[a][i].first] = Add(offset, all_queries[a][i].second);
}

int GetDistance(const int i, const int j) {
  return min(Add(i, Negate(j)), Add(j, Negate(i)));
}

int main() {
  const int node = MyNodeId();
  const int nodes = NumberOfNodes();

  n = NumberOfStudents();

  set<int> query_points;
  for (int i = 1; i <= NumberOfQueries(); ++i) {
    query_points.insert(QueryFrom(i));
    query_points.insert(QueryTo(i));
  }

  vector<pair<int, int> > cursors;
  BuildCursors(&cursors);

  // Data gathered by a worker.
  vector<Edge> edges;
  vector<Query> queries;

  // Go over my cursors.
  for (int i = node; i < cursors.size(); i += nodes) {
    pair<int, int> cursor = cursors[i];
    int offset = 0;
    while (true) {
      // Advance cursor.
      const int first = FirstNeighbor(cursor.second);
      const int second = SecondNeighbor(cursor.second);
      if (first != cursor.first) {
        cursor = make_pair(cursor.second, first);
      } else {
        cursor = make_pair(cursor.second, second);
      }
      ++offset;
      // Note if we found any queries.
      if (query_points.find(cursor.first) != query_points.end()) queries.push_back(Query(i, cursor.first, offset));
      // Note if we found any cursors.
      const vector<pair<int, int> >::const_iterator it = lower_bound(cursors.begin(), cursors.end(), cursor);
      if (it != cursors.end() && *it == cursor) {
        edges.push_back(Edge(i, it - cursors.begin(), offset));
        break;
      }
    }
  }

  // Send a report to zero.
  //
  // Relations between cursors.
  PutInt(0, edges.size());
  for (int i = 0; i < edges.size(); ++i) {
    PutInt(0, edges[i].from);
    PutInt(0, edges[i].to);
    PutInt(0, edges[i].offset);
  }
  // Queries encountered.
  PutInt(0, queries.size());
  for (int i = 0; i < queries.size(); ++i) {
    PutInt(0, queries[i].cursor);
    PutInt(0, queries[i].student);
    PutInt(0, queries[i].offset);
  }
  Send(0);

  if (node == 0) {
    // Total information from all workers.
    vector<vector<pair<int, int> > > all_edges(cursors.size());
    vector<vector<pair<int, int> > > all_queries(cursors.size());

    // Process worker messages one by one.
    for (int i = 0; i < nodes; ++i) {
      Receive(i);
      // Relations between cursors.
      const int edges_size = GetInt(i);
      for (int j = 0; j < edges_size; ++j) {
        const int from = GetInt(i);
        const int to = GetInt(i);
        const int offset = GetInt(i);
        all_edges[from].push_back(make_pair(to, offset));
        all_edges[to].push_back(make_pair(from, Negate(offset)));
      }
      // Queries encountered.
      const int queries_size = GetInt(i);
      for (int j = 0; j < queries_size; ++j) {
        const int cursor = GetInt(i);
        const int student = GetInt(i);
        const int offset = GetInt(i);
        all_queries[cursor].push_back(make_pair(student, offset));
      }
    }

    // Compute query offsets.
    map<int, int> query_offsets;
    vector<bool> visited(cursors.size(), false);
    DFS(0, 0, all_edges, all_queries, &visited, &query_offsets);
    // Print out the answers.
    for (int i = 1; i <= NumberOfQueries(); ++i) printf("%d\n", GetDistance(query_offsets[QueryFrom(i)], query_offsets[QueryTo(i)]));
  }

  return 0;
}