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#include "kollib.h"
#include "message.h"
#include <algorithm>
#include <vector>
#include <cstdlib>
#include <unordered_map>
using namespace std;

unordered_map<int, int> map;
int n, m;

int getNumber(int k)
{
    if(map.count(k)) return map[k];
    int s = k, prev = FirstNeighbor(k), i1, i2;
    for(i1 = 0; ; i1++)
    {
	int neigh = FirstNeighbor(k);
	if(neigh == prev) neigh = SecondNeighbor(k);
	prev = k;
	k = neigh;
	if(map.count(k)) break;
    }
    swap(s, k);
    prev = SecondNeighbor(k);
    for(i2 = 0; ; i2++)
    {
	int neigh = FirstNeighbor(k);
	if(neigh == prev) neigh = SecondNeighbor(k);
	prev = k;
	k = neigh;
	if(map.count(k)) break;
    }
    int v1 = map[s], v2 = map[k];
    if(v1 > v2) return v1 - i1;
    else return v2 - i2;
}

int main()
{
    if(MyNodeId()) return 0;
    
    n = NumberOfStudents();
    m = NumberOfQueries();
    int step = max(1, n / 1000);
    int k = 1, prev = FirstNeighbor(k), c = 0, p = step;
    while(true)
    {
	if(p == step)
	{
	    p = 0;
	    map.insert(make_pair(k, c));
	}
	p++;
	int neigh = FirstNeighbor(k);
	if(neigh == prev) neigh = SecondNeighbor(k);
	if(neigh == 1)
	{
	    map.insert(make_pair(k, c));
	    break;
	}
	prev = k;
	k = neigh;
	c++;
    }
    
    for(int i = 1; i <= m; i++)
    {
	int ans = abs(getNumber(QueryFrom(i)) - getNumber(QueryTo(i)));
	printf("%d\n", min(ans, n - ans));
    }
}