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#include <unordered_set>
#include <unordered_map>
#include <functional>
#include <algorithm>
//#include <iostream>
#include <numeric>
#include <cassert>
#include <cstring>
#include <cstdio>
#include <vector>
#include <queue>
//#include <cmath>
#include <set>
#include <map>
using namespace std;

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

typedef long long LL;
typedef unsigned long long ULL;
typedef vector<int> VI;
typedef vector<LL> VLL;
typedef vector<VI> VVI;
typedef pair<int,int> PII;
typedef vector<PII> VPII;

#define REP(i,n) for(int i=0;i<(n);++i)
#define FOR(i,b,e) for(int i=(b);i<=(e);++i)
#define FORD(i,b,e) for(int i=(b);i>=(e);--i)

#define PB push_back
#define ALL(V) (V).begin(),(V).end()
#define SIZE(V) ((int)(V).size())

#define MP make_pair
#define ST first
#define ND second

#define DBG

#ifdef DBG
	#define debug(...) fprintf(stderr, __VA_ARGS__)
#else
	#define debug(...)
#endif

int __stmp;
#define scanf __stmp=scanf


const int INF = 1000000001;
const int MAX = 100000;
const int MAXM = 210;
const int T = 10000;

PII Q[MAXM];

int n, m;

int main(int argc, char *argv[]) {
	int nodes = NumberOfNodes();
	int id = MyNodeId();
	n = NumberOfStudents();
	m = NumberOfQueries();
	unordered_set<int> S;
	REP(i,m)
	{
		Q[i] = PII(QueryFrom(i+1), QueryTo(i+1));
		S.insert(Q[i].ST);
		S.insert(Q[i].ND);
	}
	mt19937_64 gen(4327822);
	uniform_int_distribution<int> rd(1, n);
	REP(foo,T)
		S.insert(rd(gen));
	VI P(ALL(S));
	for(int i=SIZE(P)-1;i>0;i--)
		swap(P[i], P[uniform_int_distribution<int>(0, i)(gen)]);
	
	unordered_map<int,PII> G[2];
	
	for(int i=id;i<SIZE(P);i+=nodes)
	{
		if(id) {
			PutInt(0, P[i]);
		}
		REP(k,2)
		{
			int prv = P[i];
			int u = !k ? FirstNeighbor(P[i]) : SecondNeighbor(P[i]);
			int d = 1;
			while(!S.count(u))
			{
				d++;
				int t = u;
				u = FirstNeighbor(u) + SecondNeighbor(u) - prv;
				prv = t;
			}
			if(!id) {
				G[k][P[i]] = PII(u, d);
			} else {
				PutInt(0, u);
				PutInt(0, d);
			}
		}
	}
	if(id) {
		PutInt(0, 0);
		Send(0);
		return 0;
	}
	
	for(int s=1;s<nodes;s++)
	{
		Receive(s);
		for(int u=GetInt(s);u;u=GetInt(s))
		{
			REP(k,2)
			{
				int v = GetInt(s);
				int d = GetInt(s);
				G[k][u] = PII(v, d);
			}
		}
	}
	
	REP(i,m)
	{
		int res = 0;
		int u = Q[i].ST;
		int prv = -1;
		while(u != Q[i].ND)
		{
			PII v1 = G[0][u];
			PII v2 = G[1][u];
			if(v1.ST == prv) swap(v1, v2);
			res += v1.ND;
			prv = u;
			u = v1.ST;
		}
		printf("%d\n", min(res, n-res));
	}
	return 0;
}