#include <fstream>
#include <vector>
#include <bitset>

using namespace std;

#define MAX_N 100005
#define MAX_M 2000005

#define foreach(V) for(typeof (V).begin() it = (V).begin(); it != (V).end(); ++it)
#define nod first
#define ord second

ifstream fin ("lca.in");
ofstream fout ("lca.out");

struct nr
{
	unsigned int i : 17;
} __attribute__((packed));

int N, M, Sol[MAX_M], T[MAX_N], Str[MAX_N];
short R[MAX_N];
vector <nr> G[MAX_N];
vector <pair<nr, int> >Q[MAX_N];
bitset <MAX_N> viz;

void citire()
{
	fin >> N >> M;

	for(int i = 2; i <= N; ++i)
	{
		int a;
		nr x;
		fin >> a;
		x.i = i;

		G[a].push_back(x);
	}

	for(int i = 1; i <= M; ++i)
	{
		int a, b;
		nr x, y;
		fin >> a >> b;
		x.i = a, y.i = b;

		Q[x.i].push_back(make_pair(y, i));
		Q[y.i].push_back(make_pair(x, i));
	}
}

void unite(int x, int y)
{
	if(R[x] > R[y])
		T[y] = x;
	else
		T[x] = y;

	if(R[x] == R[y]) ++R[y];
}

int find(int x)
{
	int R, y;
	for(R = x; R != T[R]; R = T[R]);

	while(x != T[x])
	{
		y = T[x];
		T[x] = R;
		x = y;
	}

	return R;
}

void dfs(int nod)
{
	T[nod] = nod;
	Str[nod] = nod;

	foreach(G[nod])
	{
		int act = it -> i;
		dfs(act);

		unite(find(act), find(nod));
		Str[find(nod)] = nod;
	}

	viz[nod] = 1;
	foreach(Q[nod])
		if(viz[it -> nod.i])
			Sol[it -> ord] = Str[find(it -> nod.i)];
}

int main()
{
	citire();
	dfs(1);
	for(int i = 1; i <= M; ++i)
		fout << Sol[i] << "\n";
}