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#include <iostream>
#include <cstdio>
#include <algorithm>
#include <vector>
#include <list>
#include <queue>
#include <stack>
#include <map>
#include <set>
#include <cmath>
#include <string>
#include <cstring>
#include <unordered_map>

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

using namespace std;

typedef long long int LL;
typedef long double LD;
typedef vector<int> VI;
typedef vector<LL> VLL;
typedef vector<LD> VLD;
typedef vector<string> VS;
typedef pair<int, int> PII;
typedef vector<PII> VPII;

const int INF = 1000000001;
const LD EPS = 10e-9;

#define FOR(x, b, e) for(int x = b; x <= (e); ++x)
#define FORD(x, b, e) for(int x = b; x >= (e); --x)
#define REP(x, n) for(int x = 0; x < (n); ++x)
#define VAR(v, n) __typeof(n) v = (n)
#define ALL(c) (c).begin(), (c).end()
#define SIZE(x) ((int)(x).size())
#define FORE(i, c) for(VAR(i, (c).begin()); i != (c).end(); ++i)
#define MP make_pair
#define PB push_back
#define ST first
#define ND second
#define abs(a) ((a)<0 ? -(a) : (a))
#define max(a, b) ((a) > (b) ? (a) : (b))
#define min(a, b) ((a) < (b) ? (a) : (b))

const int MAX_SINGLE = 1000005;

const int MAX_Q = 500;

struct queryAnswer
{
	int query, student, pos, to;
	
	queryAnswer(int q = 0, int s = 0, int p = 0, int t = 0) : query(q), student(s), pos(p), to(t) {};
};

bool operator<(const queryAnswer &a, const queryAnswer &b)
{
	if(a.query == b.query)
	{
		if(a.student == b.student) return a.to < b.to;
		return a.student < b.student;
	}
	return a.query < b.query;
}

void propagate(int target, int student, int lastStudent, int pos)
{
	PutInt(target, student);
	PutInt(target, lastStudent);
	PutInt(target, pos);
	Send(target);	
}

/* funkcje dla mastera (node == 0) */

void queryNode(int target, int x)
{
	PutInt(target, x);
	Send(target);
}

void waitNodesReady()
{
	int s1 = Receive(-1);
	int m1 = GetInt(s1);
	
	int s2 = Receive(-1);
	int m2 = GetInt(s2);	
}

void closeNode(int target)
{
	PutInt(target, -1);
	Send(target);
}

queryAnswer getAnswer()
{
	int s = Receive(-1);
	queryAnswer res;
	
	res.query = GetInt(s);
	res.student = GetInt(s);
	res.pos = GetInt(s);
	res.to = GetInt(s);
	
	return res;
}

/* ----------------------------- */


/* funkcje dla reszty (node > 0) */

void getStartElem(int &student, int &last, int &pos)
{
	int s = Receive(-1);
	student = GetInt(s);
	last = GetInt(s);
	pos = GetInt(s);
}

void reportReady()
{
	PutInt(0, -1);
	Send(0);
}

int getMessage()
{
	Receive(0);
	return GetInt(0);	
}

void sendAnswer(const queryAnswer &qa)
{
	PutInt(0, qa.query);
	PutInt(0, qa.student);
	PutInt(0, qa.pos);
	PutInt(0, qa.to);
	
	Send(0);
}

/* ----------------------------- */

int main()
{
	int n = NumberOfStudents();
	if(n < MAX_SINGLE)
	{
		if(MyNodeId() == 0)
		{
			//cout << "1" << endl;
			
			int last, last2 = 1;
			int *pos = new int[n+5];
			pos[1] = 0;
			last = FirstNeighbor(1);
			pos[last] = 1;
			
			//cout << "2" << endl;
			
			FOR(i, 2, n-1)
			{
				int a = FirstNeighbor(last);	
				
				if(a == last2)
				{
					a = SecondNeighbor(last);
				}
				
				pos[a] = i;
				last2 = last;
				last = a;
			}
			
			//cout << "3" << endl;
			
			int qc = NumberOfQueries();
			REP(i, qc)
			{
				int x = QueryFrom(i+1);
				int y = QueryTo(i+1);
				
				int d1 = abs(pos[x]-pos[y]);
				
				cout << min(d1, n-d1) << endl;	
			}
			
			//cout << "4" << endl;
			
			delete [] pos;
		}	
		
		return 0;
	}
	
	int nodes = NumberOfNodes();
	int studentsPerNode = n/nodes;
	
	int myNode = MyNodeId();
	
	// master comp :)
	if(myNode == 0)
	{
		//cout << "master start" << endl;
		int lastRight = nodes/2;
		int myStudents = n%nodes;
		
		if(myStudents == 0)
		{
			myStudents = studentsPerNode;
		}	
		
		int actPos = 0;
		int last, last2 = 1;
		last = SecondNeighbor(1);
		unordered_map<int, int> pos;
		pos[1] = 0;
		
		// nastepny fragment po 'prawej'
		propagate(1, FirstNeighbor(1), 1, 1);
		//cout << "wypuszczono na prawo" << endl;
		
		FOR(i, 1, myStudents-1)
		{
			pos[last] = actPos = -i;
			
			//cout << "mstudent: " << last << ", pos:" << pos[last] << endl;
				
			int next = FirstNeighbor(last);	
			if(next == last2)
			{
				next = SecondNeighbor(last);
			}	
			
			last2 = last;
			last = next;
		}	
		
		// nastepny fragment po 'lewej'
		propagate(nodes-1, last, last2, actPos-1);
		//cout << "wypuszczono na prawo" << endl;
		
		//waitNodesReady();
		
		// odpowiadanie na te zapytania, na ktore moze
		queryAnswer qAns[MAX_Q];
		int qc = NumberOfQueries();
		int qAnsC = 0;
		//cout << "main q: "<< qc << endl;
		REP(i, qc)
		{
			//cout << "main q_i: " << i << endl;
			int x = QueryFrom(i+1);
			int y = QueryTo(i+1);
			
			int posX, posY;
			
			unordered_map<int, int>::iterator pX = pos.find(x);
			if(pX != pos.end())
			{
				//cout << "mx: " << x << ", pos: " << pX->second << endl;
				posX = pX->second;
				qAns[qAnsC] = queryAnswer(i, x, posX, 0);
				qAnsC++;
			}
			
			unordered_map<int, int>::iterator pY = pos.find(y);
			if(pY != pos.end())
			{
				//cout << "my: " << y << ", pos: " << pY->second << endl;
				posY = pY->second;
				qAns[qAnsC] = queryAnswer(i, y, posY, 1);
				qAnsC++;
			}
			
			//int d1 = abs(posY-posX);
			//cout << min(d1, n-d1) << endl;	
		}	
		
		// zbieranie reszty odpowiedzi
		//cout << "master zaczyna zbierac odpowiedzi" << endl;
		while(qAnsC < 2*qc)
		{
			//cout << "qAnsC na wejsciu: " << qAnsC << ", 2*qc: " << 2*qc << endl;
			qAns[qAnsC] = getAnswer();
			//cout << "query: " << qAns[qAnsC].query << ", student: " << qAns[qAnsC].student << ", pos: " << qAns[qAnsC].pos << ", to: " << qAns[qAnsC].to << endl;
			qAnsC++;
			//cout << "qAnsC: " << qAnsC << ", 2*qc: " << 2*qc << endl;	
		}
		
		//cout << "qAnsC po petli: " << qAnsC << ", 2*q: " << 2*qc << endl;	
		//cout << "master zaczyna odpowiadac" << endl;
		sort(qAns, qAns+qAnsC);
		// i odpowiadanie na zapytania
		for(int i = 0; i < 2*qc; i += 2)
		{
			//cout << "q[i]: " << qAns[i].query << ", pos: " << qAns[i].pos << ", q[i+1]: " << qAns[i+1].query << ", pos: " << qAns[i+1].pos << endl;
			int d1 = abs(qAns[i].pos-qAns[i+1].pos);
			cout << min(d1, n-d1) << endl;
		}
		
		return 0;
		
		// wylaczanie reszty instancji
		/*FOR(i, 1, nodes-1)
		{
			closeNode(i);
		}*/
	}
	else
	{
		// przetworzenie swojego przedzialu
		unordered_map<int, int> pos;
		
		int student, last, actPos;
		getStartElem(student, last, actPos);
		REP(i, studentsPerNode)
		{
			if(abs(actPos) > n-abs(actPos))
			{
				pos[student] = n-abs(actPos);
			}
			else pos[student] = actPos;
			
			//cout << "node: " << myNode <<  ", student: " << student << ", pos: " << pos[student] << endl;
			
			int next = FirstNeighbor(student);	
			if(next == last)
			{
				next = SecondNeighbor(student);
			}	
			last = student;
			student = next;
			
			if(actPos < 0) actPos--;
			else actPos++;	
		}	
		
		if(myNode < nodes/2)
		{
			propagate(myNode+1, student, last, actPos);
		}	
		else if(myNode > (nodes/2)+1)
		{
			propagate(myNode-1, student, last, actPos);	
		}
		else
		{
			// koncowe instancje zglaszaja gotowosc
			// reportReady();	
		}
		
		//cout << "zrobione przedzialy przez node: " << myNode << endl;
		
		/*int msg;
		while(msg = getMessage())
		{
			// koniec pracy :)
			if(msg == -1)
			{
				return 0;	
			}	
			
			// obrobka zapytania
			unordered_map<int, int>::iterator pX = pos.find(msg);
			if(pX != pos.end())
			{
				answerQuery(pX->second);	
			}
		}*/
		
		// odpowiadanie na zapytania na ktore moze
		int qc = NumberOfQueries();
		//cout << "q: "<< qc << endl;
		REP(i, qc)
		{
			//cout << "q_i: " << i << endl;
			int x = QueryFrom(i+1);
			int y = QueryTo(i+1);
			
			int posX, posY;
			
			unordered_map<int, int>::iterator pX = pos.find(x);
			if(pX != pos.end())
			{
				//cout << "x: " << x << ", pos: " << pX->second << endl;
				sendAnswer(queryAnswer(i, x, pX->second, 0));
			}
			
			unordered_map<int, int>::iterator pY = pos.find(y);
			if(pY != pos.end())
			{
				//cout << "y: " << y << ", pos: " << pY->second << endl;
				sendAnswer(queryAnswer(i, y, pY->second, 1));
			}
			
			//int d1 = abs(posY-posX);
			//cout << min(d1, n-d1) << endl;	
		}	
		
		//cout << "koniec node: " << myNode << endl;
		//system("pause");
		// koniec :)
		return 0;
	}
	//system("pause");
	return 0;
}