#include <fstream>
#include <iostream>
#include <vector>
#include <cmath>
const int NMAX=250005;
const int LGMAX=32;
const int LOG=18;

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

vector <int> v[NMAX];
int dp[LGMAX][NMAX];
int in[NMAX], out[NMAX];
int n, q, timp;

void build();
int LCA(int, int);
void dfs(int);
bool is_anc(int, int);

int main()
{
    ios_base::sync_with_stdio(false);
    fin.tie(0);
    fout.tie(0);
    int i, a, b;
    fin>>n>>q;
    for(i=2; i<=n; i++)
    {
        fin>>dp[0][i];
        v[dp[0][i]].push_back(i);
    }
    dp[0][1]=1;
    build();
    while(q--)
    {
        fin>>a>>b;
        fout<<LCA(a, b)<<'\n';
    }
    return 0;
}

void dfs(int nod)
{
    in[nod]=++timp;
    for(auto i:v[nod])
        dfs(i);
    out[nod]=++timp;
}

bool is_anc(int a, int b)
{
    return (in[a]<in[b] && out[a]>out[b]);
}

int LCA(int a, int b)
{
    int j;
    if(is_anc(a, b)) return a;
    if(is_anc(b, a)) return b;
    for(j=LOG; j>=0; j--)
    {
        if(!is_anc(dp[j][a], b))
            a=dp[j][a];
    }
    return dp[0][a];
}

void build()
{
    int i, j;
    dfs(1);
    for(i=1; (1<<i)<=n; i++)
    {
        for(j=1; j<=n; j++) dp[i][j]=dp[i-1][dp[i-1][j]];
    }
}