#include <bits/stdc++.h>

using namespace std;

ifstream fin("lca.in");
ofstream fout("lca.out");
const int Max = 18;
int n, q, i, tin[100002], tout[100002];
int stramos[100002][20];
vector<int> a[100002];

static inline void InitStramosii() {
    for(int b = 1; b <= Max; b++) {
        for(int i = 1; i <= n; i++) stramos[i][b] = stramos[stramos[i][b - 1]][b - 1];
    }
}

int timp = 0;
static inline void InitTimp(int nod = 1, int last = 0) {
    timp++;
    tin[nod] = timp;
    for(auto it : a[nod]) {
        if(nod != last) InitTimp(it, nod);
    }
    tout[nod] = timp;
}

static inline bool IsStramos(int a, int b) {
    return (tin[a] <= tin[b] && tout[a] >= tout[b]);
}

static inline int LCA(int x, int y) {
    if(IsStramos(x, y)) return x;
    if(IsStramos(y, x)) return y;

    for(int p = Max; p >= 0; p--) {
        int z = stramos[x][p];
        if(z != 0 && !IsStramos(z, y)) x = z;
    }
    return stramos[x][0];
}

int main() {
    fin >> n >> q;
    for(i = 2; i <= n; i++) {
        fin >> stramos[i][0];
        a[stramos[i][0]].push_back(i);
    }

    InitStramosii();
    InitTimp();

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

    return 0;
}