#include <bits/stdc++.h>
//Soltan Cristian
#define fri(a, b) for (int i = (a); i < (b); ++i)
#define frj(a, b) for(int j = a; j < b; j++)
#define frk(a, b) for(int k = a; k < b; k++)
#define frm(a, b, i) for(int i = b; i >= a; i--)
#define ll long long
#define all(x) x.begin(), x.end()
#define mod 1000000007
#define pb push_back
#define st first
#define nd second
#define sz(x) (ll)x.size()
#define rall(x) x.rbegin(), x.rend()
#define ct(x) cout << x
#define cts(x) cout << x << ' '
#define ctn(x) cout << x << '\n'
#define Y cout << "YES" << '\n'
#define N cout << "NO" << '\n'
using namespace std;
using vi = vector<int>;
using vl = vector<ll>;
using vs = vector<string>;
using vb = vector<bool>;
using ml = map<ll, ll>;
using vii = vector<vector<int>>;
using vll = vector<vector<ll>>;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
const int dx[] = {-1, 0, 1, 0};
const int dy[] = {0, 1, 0, -1};
template <typename T>void read(T n, vector<T> &a){fri(0, n){cin >> a[i];}}
template<typename T>void print(T n, T m, vector<vector<T>> &dp){fri(0, n){ct('\n');frj(0, m){ct(setw(5));cts(dp[i][j]);}}}



const int mxa = 1e5 + 1;
string __fname = "lca";  
ifstream in(__fname + ".in"); 
ofstream out (__fname + ".out"); 
#define cin in 
#define cout out

vii adj(mxa);
vi height(mxa);
vi euler;
vi first(mxa);

void dfs(int u, int v, int h){
    first[u] = sz(euler);
    height[u] = h;
    euler.pb(u);
    for(auto i : adj[u]){
        if(i != v){
            dfs(i, u, h + 1);
            euler.pb(u);
        }
    }
}

void solve(){
	int n, m;
    cin >> n >> m;
    fri(0, n - 1){
        int x;
        cin >> x;
        adj[x].pb(i + 2);
    }
    // cout << sz(euler) << '\n';
    dfs(1, -1, 1);
    // cout << " a";
    // fri(0, n){
    //     cout << first[i] << '\n';
    // }
    int sparse[sz(euler) + 1][26];
    fri(0, sz(euler)){
        // cout << euler[i] << ' ';
        sparse[i][0] = euler[i];
    }
    for(int i = 1; i <= 25; i++){
        for(int j = 0; j + (1 << (i))  <= sz(euler); j++){
            if(height[sparse[j][i - 1]] < height[sparse[j + (1 << (i - 1))][i - 1]]){
                sparse[j][i] = sparse[j][i - 1];
            }
            else {
                sparse[j][i] = sparse[j + (1 << (i - 1))][i - 1];    
            }
        }
    }
    // cout << "1" << '\n';
    fri(0, m){
        int a, b;
        cin >> a >> b;
        a = first[a];
        b = first[b];
        if(a > b){
            swap(a, b);
        }
        int j = (int)log2(b - a + 1);
        if(height[sparse[a][j]] < height[sparse[b - (1 << j) + 1][j]]){
            cout << sparse[a][j] << '\n';
        }
        else cout << sparse[b - (1 << j) + 1][j] << '\n';
    }
}


int main()
{   
    ios_base::sync_with_stdio(0); cin.tie(0); ct(fixed); ct(setprecision(10)); 
    // int t;
    // cin >> t;
    // while(t--)
        solve();
    return 0;
}