#include <fstream>
#include <iostream>
#include <vector>
#define NMAX 100000

using namespace std;

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

int n, m, dist[NMAX+10][20], level[NMAX+10];
vector <int> fiu[NMAX+10];

void dfs(int nod, int tata)
{   level[nod] = level[tata] + 1;
    for(int i=0; i<fiu[nod].size(); i++)
    if(fiu[nod][i] != tata) dfs(fiu[nod][i], nod);
}

int lca(int x, int y)
{   if(level[x] < level[y]) swap(x, y);
    int dif = level[x] - level[y];
    for(int i=0; (1<<i)<=dif; i++) if(dif & (1 << i)) x = dist[x][i];
    if(x == y) return x;
    for(int i=18; i>=0; i--)
        if(dist[x][i] && dist[y][i] && dist[x][i] != dist[y][i]) x = dist[x][i], y = dist[y][i];
    return dist[x][0];
}

int main()
{
    f >> n >> m;
    for(int i=2; i<=n; i++)
        {   f >> dist[i][0];
            fiu[dist[i][0]].push_back(i);
        }
    dfs(1, 0);
    for(int i=1; (1<<i)<=n; i++)
        for(int j=1; j<=n; j++) dist[j][i] = dist[dist[j][i-1]][i-1];
    for(int i=1; i<=m; i++)
        {   int x, y;
            f >> x >> y;
            g << lca(x, y) << '\n';
        }
    return 0;
}