#include <fstream>
#include <vector>
using namespace std;

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

int n, m, a[20][100001], lg2[100001], lvl[100001];
vector<int> g[100001];

void read()
{
	in >> n >> m;
	for(int i = 2; i <= n; ++i)
		in >> a[0][i],
		g[a[0][i]].push_back(i);
}

void prec()
{
	for(int i = 2; i <= n; ++i)
		lg2[i] = lg2[i/2] + 1;
	for(int i = 1; (1<<i) <= n; ++i)
		for(int j = 1; j <= n; ++j)
			a[i][j] = a[i-1][a[i-1][j]];
}

void dfs(int nod)
{
	for(auto i : g[nod])
		lvl[i] = lvl[nod] + 1,
		dfs(i);
}

int lca(int x, int y)
{
	if(lvl[x] < lvl[y])
		swap(x, y);
	while(lvl[x] != lvl[y])
		x = a[lg2[lvl[x] - lvl[y]]][x];
	if(x == y)
		return x;

	for(int i = lg2[lvl[x]]; i >= 0; --i)
		if(a[i][x] != a[i][y])
			x = a[i][x],
			y = a[i][y];
	return a[0][x];
}

void afis()
{
	dfs(1);
	int x, y;
	while(m--)
		in >> x >> y,
		out << lca(x, y) << '\n';
}

int main()
{
	read();
	prec();
	afis();
	return 0;
}