#include <bits/stdc++.h>

using namespace std;

ifstream fin("lca.in");
ofstream fout("lca.out");
int n, q, i, p[100002][20], x, y;
int tIn[100002], tOut[100002];
vector<int> g[100002];

int timp = 0;
static inline void Parc(int nod = 1, int tata = 0) {
    tIn[nod] = ++timp;
    for(int urm : g[nod]) {
        if(urm != tata) Parc(urm, nod);
    }
    tOut[nod] = ++timp;
}

static inline void Precalc() {
    for(int put = 1; put < 20; put++) {
        for(int i = 1; i <= n; i++) p[i][put] = p[p[i][put - 1]][put - 1];
    }
}

static inline bool Subarb(int tata, int nod) {
    return tIn[tata] <= tIn[nod] && tOut[tata] >= tOut[nod];
}

static inline int Calc(int x, int y) {
    if(Subarb(x, y)) return x;
    if(Subarb(y, x)) return y;

    for(int put = 19; put >= 0; put--) {
        int z = p[x][put];
        if(z != 0 && !Subarb(z, y)) x = z;
    }
    return p[x][0];
}

int main() {
    ios_base::sync_with_stdio(false);
    fin.tie(nullptr);
    fout.tie(nullptr);

    fin >> n >> q;
    for(i = 2; i <= n; i++) {
        int t;
        fin >> t;
        p[i][0] = t;
        g[t].push_back(i);
    }

    Parc();
    Precalc();

    while(q--) {
        fin >> x >> y;
        fout << Calc(x, y) << "\n";
    }

    return 0;
}