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//	#define DEBUG
#ifdef DEBUG
#define D(...) __VA_ARGS__
#else
#define D(...) do {} while(0)
#define NDEBUG
#endif

#include <iostream>
#include <random>
#include <map>
#include <set>
#include <array>
#include <assert.h>

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

using namespace std;

map<int, int> checkpoints;
set<int> targets;
map<int, int> found_targets;

struct Neighbour
{
	int neighbour;
	int distance;
};
struct Node
{
	array<Neighbour,2> neighbours;
	int distance;
	int visited;
	int dir;
};
vector<Node> nodes;
struct TargetDesc
{
	int node;
	int distance;
};
map<int,vector<TargetDesc>> target_descs;

typedef int (*StepFunction)(int);

struct SidewaysGoer
{
	int pos, ppos, pppos, distance, direction, neighbour;
	StepFunction primary, secondary;

	SidewaysGoer(int start, int direction)
		: pos      (start)
		, ppos     (0)
		, pppos    (0)
		, distance (0)
		, direction(direction)
		, neighbour(0)
		, primary  (direction == 1  ? FirstNeighbor : SecondNeighbor)
		, secondary(direction == -1 ? FirstNeighbor : SecondNeighbor)
	{
		assert(direction == -1 || direction == 1);
		check_targets();
	}

	bool arrived()
	{
		return neighbour != 0;
	}

	void check_checkpoints()
	{
		auto cp = checkpoints.find(pos);
		if(cp != checkpoints.end())
		{
			D(cerr << "arrived at checkpoint of node " << cp->second << endl);
			neighbour = cp->second;
		}
	}

	void check_targets()
	{
		auto src = targets.find(pos);
		if(src != targets.end())
		{
			D(cerr << "found target " << pos << endl);
			found_targets[pos] = distance;
		}
	}

	void go()
	{
		pppos = ppos;
		ppos = pos;
		pos = primary(ppos);
		assert(pos != ppos);
		if(pos == pppos)
		{
			pos = secondary(ppos);
			swap(primary, secondary);
		}
		D(cerr << "goer " << direction << "\t" << pppos << " " << ppos << " " << pos << endl);
		distance += direction;
		check_targets();
		check_checkpoints();
	}
};

int main(int argc, char **argv)
{
	ios_base::sync_with_stdio(false);

	int seed;
	int me = MyNodeId();
	int n_nodes = NumberOfNodes();
	int n_students = NumberOfStudents();
	int n_queries = NumberOfQueries();
	if(me == 0)
	{
		random_device rd;
		mt19937 mt(rd());
		uniform_int_distribution<int> d(1, n_students);
		int i;
		for(i=1; i<n_nodes; i++)
		{
			int first_s = d(mt);
			D(cerr << "node " << i << " maybe will have " << first_s << endl);
			bool first = true, awarded = false;
			int s;
			for(s = first_s; !awarded && (s != first_s || first); s=(s%n_students)+1)
			{
				first = false;
				auto &cp = checkpoints[s];
				if(cp == 0)
				{
					D(cerr << "node " << i << " has got " << s << endl);
					cp = i;
					awarded = true;
				}
			}
			if(!awarded)
			{
				// this will happen only if there are more worker nodes than students
				break;
			}
		}
		int active_worker_nodes = i - 1; // remember how many nodes are active
		assert(active_worker_nodes <= n_students); // and assert the above assumption
		for(int i=1; i<n_nodes; i++)
		{
			PutInt(i, checkpoints.size());
			for(auto &cp: checkpoints)
			{
				PutInt(i, cp.first);
				PutInt(i, cp.second);
			}
			Send(i);
		}
		nodes.resize(active_worker_nodes + 1);
		D(cerr << "active worker nodes: " << active_worker_nodes << endl);
		for(int i=0; i<active_worker_nodes; i++)
		{
			int node = Receive(-1);
			auto &N = nodes[node].neighbours;
			assert(N[0].neighbour == 0);
			assert(N[1].neighbour == 0);
			N[0].neighbour = GetInt(node);
			N[0].distance = GetInt(node);
			N[1].neighbour = GetInt(node);
			N[1].distance = GetInt(node);
			D(cerr << "from " << node << " got " << N[0].neighbour << " " << N[0].distance << " " << N[1].neighbour << " " << N[1].distance << endl);
			int S;
			S = GetInt(node);
			for(int j=0; j<S; j++)
			{
				int pos = GetInt(node);
				int distance = GetInt(node);
				target_descs[pos].push_back({node, distance});
			}
		}
		D(cerr << "got data back from all active nodes" << endl);

		int cur_i=1;
		nodes[cur_i].dir = false;
		nodes[cur_i].visited = 1;
		do
		{
			D(cerr << "I'm at " << cur_i << endl);
			auto &cur = nodes[cur_i];
			assert(cur.visited == 1);
			cur.visited = 2;
			auto &next_n = cur.neighbours[cur.dir];
			int next_i = next_n.neighbour;
			assert(next_i != 0);
			D(cerr << "going to " << next_i << endl);
			auto &next = nodes[next_i];
			if(next.neighbours[!cur.dir].neighbour == cur_i)
			{
				next.dir = cur.dir;
				assert(next.neighbours[!cur.dir].distance == -next_n.distance);
			}
			else if(next.neighbours[cur.dir].neighbour == cur_i)
			{
				next.dir = !cur.dir;
				assert(next.neighbours[cur.dir].distance == next_n.distance);
			}
			else
			{
				abort();
			}
			int next_distance = cur.distance + (cur.dir ? -next_n.distance : next_n.distance);
			if(next_i == 1)
			{
				D(cerr << "got back to first node, finishing enumeration" << endl);
				assert(next.dir == 0);
				assert(next_distance == n_students);
			}
			else
			{
				assert(next.visited == 0);
				next.visited = 1;
				next.distance = next_distance;
			}
			cur_i = next_i;
		}
		while(cur_i != 1);

		map<int,int> distance_to_node;
		for(int i=1; i<active_worker_nodes+1; i++)
		{
			assert(nodes[i].visited == 2);
			D(cerr << "node " << i << " distance: " << nodes[i].distance << endl);
			distance_to_node[nodes[i].distance] = i;
		}

#ifdef DEBUG
		for(auto &t: target_descs)
		{
			auto &S = t.second;
			int pd;
			for(int j=0; j<S.size(); j++)
			{
				int d = nodes[S[0].node].distance + (nodes[S[0].node].dir ? -S[0].distance : S[0].distance);
				if(j > 1)
				{
					assert(pd == d);
				}
				pd = d;
			}
		}
#endif

		for(int i=1; i<=n_queries; i++)
		{
			auto &S = target_descs[QueryFrom(i)];
			auto &D = target_descs[QueryTo(i)];
			assert(!S.empty());
			assert(!D.empty());
			int sd = nodes[S[0].node].distance + (nodes[S[0].node].dir ? -S[0].distance : S[0].distance);
			int dd = nodes[D[0].node].distance + (nodes[D[0].node].dir ? -D[0].distance : D[0].distance);
			int diff = (sd - dd + n_students) % n_students;
			diff = min(diff, n_students - diff);
			cout << diff << endl;
		}
	}
	else
	{
		Receive(0);
		int n_checkpoints;
		n_checkpoints = GetInt(0);
		int my_start = 0;
		for(int i=0; i<n_checkpoints; i++)
		{
			int v, n;
			v = GetInt(0);
			n = GetInt(0);
			checkpoints[v] = n;
			if(n == me)
			{
				my_start = v;
			}
		}
		if(my_start == 0)
		{
			D(cerr << "nothing to do for me" << endl);
			return 0;
		}

		for(int i=NumberOfQueries(); i>0; i--)
		{
			targets.insert(QueryFrom(i));
			targets.insert(QueryTo(i));
		}

		D(cerr << "starting from " << my_start << endl);
		SidewaysGoer a(my_start, 1), b(my_start, -1);
		while(!a.arrived() && !b.arrived())
		{
			a.go();
			b.go();
		}
		while(!a.arrived())
		{
			a.go();
		}
		while(!b.arrived())
		{
			b.go();
		}
		assert(a.distance > 0);
		assert(b.distance < 0);
		PutInt(0, a.neighbour);
		PutInt(0, a.distance);
		PutInt(0, b.neighbour);
		PutInt(0, b.distance);
		PutInt(0, found_targets.size());
		for(auto &s: found_targets)
		{
			PutInt(0, s.first); // position
			PutInt(0, s.second); // distance
		}
		Send(0);
	}
	return 0;
}