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#include "kollib.h"
#include "message.h"
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;
vector <int> t;

pair <int, int> qu[201];

int bin_search(int x)
{
	int l = 0;
	int p = t.size() - 1;
	while(l <= p)
	{
		int s = (l + p) / 2;
		if(t[s] == x) return s;
		if(t[s] > x) p = s - 1;
		else l = s + 1;
	}
	return -1;
}

int main()
{
	int n = NumberOfStudents();
	int last = 0;
	int l = (n + NumberOfNodes() - 1) / NumberOfNodes();
	int x = 0;

	if(MyNodeId() == 0)
	{
		x = 1;
		x = FirstNeighbor(x);
	}
	else 
	{
		int instancja = Receive(-1);
		x = GetInt(instancja);
	}


	for(int i = 0; i < l && x != 1; ++i)
	{
		t.push_back(x);
		if(last == FirstNeighbor(x))
		{
			last = x;
			x = SecondNeighbor(x);
		}
		else
		{
			last = x;
			x = FirstNeighbor(x);
		}
	}

	if(MyNodeId() < NumberOfNodes() - 1)
	{
		PutInt(MyNodeId() + 1, x);
		Send(MyNodeId() + 1);
	}

	sort(t.begin(), t.end());

	int m = NumberOfQueries();

	for(int i = 0; i < m; ++i) qu[i].first = qu[i].second = -1;

	for(int i = 1; i <= m; ++i)
	{
		int a = QueryFrom(i);
		int b = QueryTo(i);
		int ap = bin_search(a);
		int bp = bin_search(b);

		if(ap != -1)
		{
			PutInt(0, i);
			PutInt(0, MyNodeId() * l + ap);
			Send(0);
		}
		if(bp != -1)
		{
			PutInt(0, i);
			PutInt(0, MyNodeId() * l + bp);
			Send(0);
		}
	}

	if(MyNodeId() == 0)
	{
		for(int i = 0; i < 2 * m; ++i)
		{
			int instancja = Receive(-1);
			int nr = GetInt(instancja);
			int wh = GetInt(instancja);
			qu[nr].second = wh;
			if(qu[nr].first == -1) qu[nr].first = qu[nr].second;
		}

		for(int i = 0; i < m; ++i)
		{
			if(qu[i].first > qu[i].second) swap(qu[i].first, qu[i].second);
			int wyn = qu[i].second - qu[i].first;
			wyn = min(wyn, n - qu[i].second + qu[i].first);
			cout << wyn << '\n';
		}
	}
	
	return 0;
}