//O(N + M * RMAX)
//RMAX = O(sqrt(N))

#include <fstream>
#include <cstring>

using namespace std;

static const int MAXN = 100009;
static const int LG = 18;
int n;
int dad[MAXN][LG];
int level[MAXN];

int getLevel(int nod)
{
	if(level[nod] == -1)
	{
		level[nod] = getLevel(dad[nod][0]) + 1;
	}
	return level[nod];
}

void compute_dads()
{
	for(int i = 1; i <= n; i++)
	{
		for(int j = 1; j < LG; j++)
		{
			dad[i][j] = dad[dad[i][j - 1]][j - 1];
		}
	}
}

int main()
{
	int m, x, y;
	ifstream f("lca.in");
	ofstream g("lca.out");
	f >> n >> m;
	dad[0][1] = 1;
	for(int i = 2; i <= n; i++)
	{
		f >> dad[i][0];
	}
	memset(level, -1, sizeof(level));
	level[1] = 0;
	for(int i = 2; i <= n; i++)
	{
		level[i] = getLevel(i);
	}
	compute_dads();
	for(int i = 0; i < m; i++)
	{
		f >> x >> y;
		if(level[x] > level[y])
		{
			for(int i = LG - 1; i >= 0; i--)
			{
				if(level[dad[x][i]] >= level[y])
				{
					x = dad[x][i];
				}
			}
		}
		if(level[y] > level[x])
		{
			for(int i = LG - 1; i >= 0; i--)
			{
				if(level[dad[y][i]] >= level[x])
				{
					y = dad[y][i];
				}
			}
		}
		if(x != y)
		{
			for(int i = LG - 1; i >= 0; i--)
			{
				if(dad[x][i] != dad[y][i])
				{
					x = dad[x][i];
					y = dad[y][i];
				}
			}
			x = dad[x][0];
			y = dad[y][0];
		}
		g << x << '\n';
	}
	f.close();
	g.close();
	return 0;
}