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#include <algorithm>
#include <cstdlib>
#include <iostream>
#include <map>
#include <set>
#include <queue>

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

using namespace std;

typedef pair<int, int> pii;

const int mmax = 200+5;

int slaves, nid;

int n, m;
set<int> qPoints;
int queryFrom[mmax], queryTo[mmax];
deque<int> order;
map<pii, int> nbdistance;
map<int, pii> neighbors;
vector< pair<pii, int> > detected;
map<int, int> nbdistanceCache;

ostream& operator<<(ostream& out, const pii& p) {
	out << '(' << p.first << ',' << p.second << ')';
	return out;
}

inline int neighbor(int sid, int away) {
	return (FirstNeighbor(sid) != away) ? FirstNeighbor(sid) : SecondNeighbor(sid);
}

pii nextNeighbor(int nb, int away) {
	int d = 1;
	while (qPoints.find(nb) == qPoints.end()) {
		int e = neighbor(nb, away); away = nb; nb = e;
		d++;
		if (d > (n/2 + 2)) { nb = 0; break; }
	}
	return make_pair(nb, d);
}

void calcNeighbors(int sid) {
	pii nb1 = nextNeighbor(FirstNeighbor(sid), sid);
	detected.push_back(make_pair(make_pair(sid, nb1.first), nb1.second));
	pii nb2 = nextNeighbor(SecondNeighbor(sid), sid);
	detected.push_back(make_pair(make_pair(sid, nb2.first), nb2.second));
}

void sendDetected() {
	PutInt(0, detected.size());
	for (auto dd : detected) {
		PutInt(0, dd.first.first);
		PutInt(0, dd.first.second);
		PutInt(0, dd.second);
	}
	Send(0);
}

struct {
	void buildOrder() {
		int first = *qPoints.begin();
		int last = neighbors[first].first, prev = first;
		order.push_back(first);
		while (last && last != first) {
			// cerr << "+" << last << "\n";
			order.push_back(last);
			int next = (neighbors[last].first != prev) ? neighbors[last].first : neighbors[last].second;
			prev = last; last = next;
		}
		
		last = neighbors[first].second, prev = first;
		while (last && last != first) {
			// cerr << "+" << last << "\n";
			order.push_front(last);
			int next = (neighbors[last].first != prev) ? neighbors[last].first : neighbors[last].second;
			prev = last; last = next;
		}
	}

	void buildDistanceCache() {
		auto it = order.begin();
		int prev = *it;
		int dist = 0;
		nbdistanceCache[*it] = 0;

		it++;
		while (it != order.end()) {
			dist += nbdistance[make_pair(prev, *it)];
			nbdistanceCache[*it] = dist;
			prev = *it;
			it++;
		}
	}

	void answerQueries() {
		// cerr << "answerQueries\n";
		buildDistanceCache();
		for (int i = 1; i <= m; i++) {
			// cerr << "query " << i << ":" << queryFrom[i] << "-" << queryTo[i] << "\n";
			int dist = abs(nbdistanceCache[queryFrom[i]] - nbdistanceCache[queryTo[i]]);
			cout << min(n-dist, dist) << "\n";
		}
	}
} node0;

int main() {
	slaves = NumberOfNodes();
	nid = MyNodeId();

	n = NumberOfStudents();
	m = NumberOfQueries();

	for (int i = 1; i <= m; i++) {
		queryFrom[i] = QueryFrom(i); queryTo[i] = QueryTo(i);
		qPoints.insert(queryFrom[i]); qPoints.insert(queryTo[i]);
	}

	int i = 0;
	
	for (set<int>::iterator it = qPoints.begin(); it != qPoints.end(); it++, i++) {
		if (i % slaves == nid) { calcNeighbors(*it); }
	}
	sendDetected();
	detected.clear();

	if (nid == 0) {
		for (int i = 0; i < slaves; i++) {
			Receive(i);
			int k = GetInt(i);
			for (int j = 0; j < k; j++) {
				int sid = GetInt(i), nb = GetInt(i), d = GetInt(i);
				// cerr << sid << " " << nb << "=" << d << "\n";
				if (nb) {
					nbdistance[make_pair(sid, nb)] = d; nbdistance[make_pair(nb, sid)] = d;
					if (neighbors.find(sid) != neighbors.end()) {
						neighbors[sid].second = nb;
					} else {
						neighbors[sid] = make_pair(nb, 0);
					}
				}
			}
		}

		// cerr << "neighbors:\n";
		// for (auto x : neighbors) {
		// 	cerr << x.first << "->" << x.second << '\n';
		// }
		// cerr << '\n';

		node0.buildOrder();

		// for (auto x : order) {
		// 	cerr << x << " ";
		// }
		// cerr << '\n';

		node0.answerQueries();
	}

	return 0;
}