#include <stdio.h>
#include <vector>
#define nmax 100010
#define SZ(x) ((int)(x.size()))

using namespace std;

int n, m;
int dp[20][nmax], lvl[nmax], parent[nmax];
vector <int> graph[nmax];

void dfs(int node, int p)
{
	lvl[node] = lvl[p] + 1; parent[node] = p;
	
	for (int i = 0; i < SZ(graph[node]); i++)
		if (graph[node][i] != p) {
			
			dfs(graph[node][i], node);
		}
}

int lca(int x, int y)
{
	if (x == y) return x;
	
	if (lvl[x] < lvl[y]) { int aux = x; x = y; y = aux; }
	
	int diff = lvl[x] - lvl[y];
	
	for (int i = 0; i < 20; i++)
		if (((diff >> i) & 1) == 1) x = dp[i][x];
		
	if (x == y) return x;
	
	for (int i = 19; i >= 0; i--)
		if (dp[i][x] != -1 && dp[i][x] != dp[i][y]) { x = dp[i][x]; y = dp[i][y]; }
		
	return parent[x];
}

int main()
{
	freopen("lca.in", "r", stdin);
	freopen("lca.out", "w", stdout);

	scanf("%d %d", &n, &m);

	for (int i = 2; i <= n; i++) {
		
		int x;
		
		scanf("%d", &x);
		
		graph[i].push_back(x);
		graph[x].push_back(i);
	}
	
	dfs(1, 0);
	
	for (int i = 0; (1 << i) <= n; i++)
		for (int j = 1; j <= n; j++)
			dp[i][j] = -1;
	
	for (int i = 1; i <= n; i++) dp[0][i] = parent[i];
	
	for (int i = 1; (1 << i) <= n; i++) {
		
		for (int j = 1; j <= n; j++) 
			if (dp[i - 1][j] != -1) dp[i][j] = dp[i - 1][dp[i - 1][j]];
	}
	
	for (int i = 1; i <= m; i++) {
		
		int x, y;
		
		scanf("%d %d", &x, &y);
		
		printf("%d\n", lca(x, y));
		
	}
	
	return 0;
}