#include <bits/stdc++.h>

using namespace std;

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

int n,k,m;
int rmq[20][100005*4];
int L[100005*2],H[100005*2],lg[100005*2],fr[100005];

vector<int>G[100005];

void dfs(int nod,int lvl)
{
    H[++k]=nod;
    L[k]=lvl;
    fr[nod]=k;
    for(auto vecin:G[nod])
    {
        dfs(vecin,lvl+1);
        H[++k]=nod;
        L[k]=lvl;
    }
}

void do_rmq()
{
    for(int i=2; i<=k; i++)
        lg[i]=lg[i/2]+1;
    for(int i=1; i<=k; i++)
    {
        rmq[0][i]=i;
    }
    for(int i=1; (1<<i)<k; i++)
        for(int j=1; j<=k-(1<<i); j++)
        {
            int l = 1 << (i - 1);

            rmq[i][j] = rmq[i-1][j];
            if(L[rmq[i-1][j + l]] < L[rmq[i][j]])
                rmq[i][j] = rmq[i-1][j + l];
        }
}

int lca(int x,int y)
{
    int diff, l, sol, sh;
	int a = fr[x];
	int b = fr[y];
	if(a > b) swap(a, b);
	diff = b - a + 1;
	l = lg[diff];
	sol = rmq[l][a];
	sh = diff - (1 << l);
	if(L[sol] > L[rmq[l][a + sh]])
		sol = rmq[l][a + sh];
	return H[sol];
}

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


    return 0;
}