#include<stdio.h>
#include<vector>
#include<algorithm>
using namespace std;

int K, N, M, x, y, L[200010], H[200010], Lg[200010], First[100010], Rmq[20][400010];
vector<int> G[100010];

void dfs(int nod, int lev)
{
    H[++K] = nod;
    L[K] = lev;
    First[nod] = K;

    int z = G[nod].size();
    for(int i=0;i<z;++i)
    {
        dfs(G[nod][i],lev+1);
        H[++K] = nod;
        L[K] = lev;
    }
}

void 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 a = First[x], b = First[y];
    if(a>b)
    {
        int c=a;
        a=b;
        b=c;
    }
    int diff = b - a + 1;
    int l = Lg[diff];
    int sol = Rmq[l][a];
    int sh = diff - (1 << l);
    if(L[sol] > L[Rmq[l][a + sh]])
        sol = Rmq[l][a + sh];
    return H[sol];
}

int main()
{
    freopen("lca.in","r",stdin);
    freopen("lca.out","w",stdout);
    scanf("%d%d",&N,&M);
    for(int i=2;i<=N;++i)
    {
        scanf("%d",&x);
        G[x].push_back(i);
    }

    dfs(1,0);
    rmq();

    for(int i=1;i<=M;++i)
    {
        scanf("%d%d",&x,&y);
        printf("%d\n",lca(x,y));
    }
    return 0;
}