#include <bits/stdc++.h>

using namespace std;

#if 1
    #define pv(x) cout<<#x<<" = "<<x<<"; ";cout.flush()
    #define pn cout<<endl
#else
    #define pv(x)
    #define pn
#endif

#ifdef ONLINE_JUDGE
    #define in cin
    #define out cout
#else
    ifstream in("lca.in");
    ofstream out("lca.out");
#endif

using ll = long long;
using ull = unsigned long long;
using ui = unsigned int;
#define pb push_back
#define mp make_pair
const int NMax = 1e5 + 5;
const ll inf_ll = 1e18 + 5;
const int inf_int = 1e9 + 5;
const int mod = 100003;
using zint = int;

int N,M,height,root;
int depth[NMax],dad[NMax],an[NMax];
vector<int> v[NMax];

void getHeight(int node) {

    for (int nxt : v[node]) {
        if (nxt == dad[node]) {
            continue;
        }

        depth[nxt] = depth[node] + 1;
        getHeight(nxt);
    }

    height = max(height, depth[node]);
}

void build(int node) {
    an[node] = (depth[node] % root == 0) ? dad[node] : an[dad[node]];

    for (int nxt : v[node]) {
        if (nxt == dad[node]) {
            continue;
        }

        build(nxt);
    }
}

int main() {
    in>>N>>M;
    for (int i = 2;i <= N;++i) {
        in>>dad[i];

        v[dad[i]].pb(i);
    }

    getHeight(1);

    for(root = 1;root*root <= height;++root) ;
    --root;

    build(1);

    while (M--) {
        int x,y;
        in>>x>>y;

        while (an[x] != an[y]) {
            if (depth[x] > depth[y]) {
                x = an[x];
            }
            else {
                y = an[y];
            }
        }

        while (x != y) {
            if (depth[x] > depth[y]) {
                x = dad[x];
            }
            else {
                y = dad[y];
            }
        }

        out<<x<<'\n';
    }

    return 0;
}