#include <cstdio>
#include <vector>
#include <algorithm>
#define NMAX 100005
#define LMAX 20
#define pb push_back
#define minim(a, b) a <= b ? a : b
using namespace std;

FILE *f = freopen("lca.in", "r", stdin);
FILE *g = freopen("lca.out", "w", stdout);

int L[NMAX <<1], Lg[NMAX << 1], H[NMAX << 1], First[NMAX];
int Rmq[LMAX][NMAX << 2];
vector <int> G[NMAX];
int N, M, K;
void readData() {
    scanf("%d%d", &N, &M);
    for(int i = 2; i<=N; i++)
    {
        int x;
        scanf("%d", &x);
        G[x].pb(i);
    }
}
void dfs(int nod, int lev) {
    H[++K] = nod;
    L[K] = lev;
    First[nod] = K;
    for(int i = 0; i<G[nod].size(); i++)
    {
        dfs(G[nod][i], lev + 1);
        H[++K] = nod;
        L[K] = lev;
    }
}
void rmq() {
    Lg[1] = 0;
    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; i<=Lg[K]; i++)
        for(int j = 1; j<= K - 1 <<(i - 1); j++)
            Rmq[i][j] = L[Rmq[i - 1][j]] < L[Rmq[i - 1][j + (1 <<(i - 1))]] ? Rmq[i - 1][j] : Rmq[i - 1][j + (1 << (i - 1))];
}
int lca(int x, int y) {
    int X = First[x], Y = First[y];
    if(X > Y) swap(X, Y);
    int K = Lg[Y - X + 1];
    int sol = L[Rmq[K][X]] < L[Rmq[K][Y - (1 << K) + 1]] ? Rmq[K][X] : Rmq[K][Y - (1 << K) + 1];

    return H[sol];
}
int main() {
    readData();
    dfs(1, 0);
    rmq();
    for(int i = 1; i<=M; i++) {
        int x, y;
        scanf("%d%d", &x, &y);
        printf("%d\n", lca(x, y));
    }
    return 0;
}