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#include <iostream>
#include "message.h"
#include "kollib.h"
#include <vector>
#include <algorithm>

class Uczen
{
	public:
	int i;
	int p;
};

bool operator < (Uczen a, Uczen b)
{
	return a.i < b.i;
}

int bs (std::vector<Uczen> A, int poczatek, int koniec, int szukane)
{
    int srodek=(poczatek+koniec)/2;
    while (A[srodek].p !=szukane && koniec-poczatek>0)
    {
        if (A[srodek].p<szukane) {poczatek=srodek+1; srodek=(poczatek+koniec)/2; }
        if (A[srodek].p>szukane) {koniec=srodek; srodek=(poczatek+koniec)/2; }
    }
    if (A[srodek].p ==szukane) return A[srodek].p;
    return -1;
}


int main()
{
	int n, m, p, prev, cur;
	m = NumberOfQueries();
	if (m == 0)
		return 0;
	n = NumberOfStudents();
	p = n / NumberOfNodes();
	if (MyNodeId() == 0)
	{
		p += n % NumberOfNodes();
		cur = 1;
		prev = FirstNeighbor(1);
		PutInt(NumberOfNodes() - 1, cur);
		PutInt(NumberOfNodes() - 1, prev);		
	}
	std::vector<Uczen> arr(p);
	if (MyNodeId() >= 0 && MyNodeId() < NumberOfNodes() / 2)
	{
		int next;
		if (MyNodeId() > 0)
		{
			Receive(MyNodeId() - 1);
			prev = GetInt(MyNodeId() - 1);
			cur = GetInt(MyNodeId() - 1);
		}
		
		for (int i = 0; i < p; i++)
		{
			if (FirstNeighbor(cur) == prev)
				next = SecondNeighbor(cur);
			else
				next = FirstNeighbor(cur);
			arr[i].i = cur;
			arr[i].p = i + p * MyNodeId();
			if (MyNodeId() > 0)
				arr[i].p += n % NumberOfNodes();
			prev = cur;
			cur = next;			
		}
		
		if (FirstNeighbor(cur) == prev)
			next = SecondNeighbor(cur);
		else
			next = FirstNeighbor(cur);
			
		if (MyNodeId() < NumberOfNodes() / 2 - 1)
		{
			PutInt(MyNodeId() + 1, cur);
			PutInt(MyNodeId() + 1, next);
			Send(MyNodeId() + 1);
		}
		std::sort(arr.begin(), arr.end());
		//////
	}
	else
	{
		int next;
		int s;
		if (MyNodeId() == NumberOfNodes() - 1)
			s = 0;
		else
			s = MyNodeId() + 1;
		Receive(s);
		prev = GetInt(s);
		cur = GetInt(s);
		for (int i = p - 1; i >= 0; i--)
		{
			if (FirstNeighbor(cur) == prev)
				next = SecondNeighbor(cur);
			else
				next = FirstNeighbor(cur);
			arr[i].i = cur;
			arr[i]. p = i;
			prev = cur;
			cur = next;			
		}
		
		if (FirstNeighbor(cur) == prev)
			next = SecondNeighbor(cur);
		else
			next = FirstNeighbor(cur);
				
		if (MyNodeId() > n / 2)
		{
			PutInt(MyNodeId() - 1, cur);
			PutInt(MyNodeId() - 1, next);
		}
		std::sort(arr.begin(), arr.end());
	}
	
	for (int i = 1; i <= m; i++)
	{
		int p1, p2, d1, d2;
		if (MyNodeId() == 0)
		{
			for (int j = 1; j < NumberOfNodes(); j++)
			{
				PutInt(j, i);
				Send(j);
			}
			p1 = bs(arr, 0, p, QueryFrom(i));
			p2 = bs(arr, 0, p, QueryTo(i));	
			if (p1 == -1)
				p1 = GetInt(Receive(-1));
			if (p2 == -1)
				p2 = GetInt(Receive(-1));
				
			if ( p1 > p2)
				std::swap(p1, p2);
			d1 = p2 - p1;
			d2 = n - p2 + p1;
			std::cout<< std::min(d1, d2)<<std::endl;
		}
		else
		{
			Receive(0);
			int j = GetInt(0);
			p1 = bs(arr, 0, p, QueryFrom(i));
			p2 = bs(arr, 0, p, QueryTo(i));
			if (p1 != -1)
			{
				PutInt(0, p1);
				Send(0);
			}
			if (p2 != -1)
			{
				PutInt(0, p2);
				Send(0);
			}
		}
	
	}
	return 0;
}