#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
using namespace std;
typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> indexed_set;
template <typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template<typename T>
using ordered_multiset = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update>;
struct custom_hash {
    static uint64_t splitmix64(uint64_t x) {
        // http://xorshift.di.unimi.it/splitmix64.c
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }

    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};

struct custom_hash_pair {
    static uint64_t splitmix64(uint64_t x) {
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }

    size_t operator()(pair<uint64_t,uint64_t> x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x.first + FIXED_RANDOM)^(splitmix64(x.second + FIXED_RANDOM) >> 1);
    }
};

#define all(x) (x).begin(), (x).end()
#define allg(x) (x).begin(), (x).end(), greater<int>()
using ull = unsigned long long;
using ll =  long long;
using ld = double;
using vi = vector<int>;
using vb = vector<bool>;
using vl = vector<ll>;
using vd = vector<ld>;
using si = set<int>;
using ssi = set<si>;
using sl = set<ll>;
using ssl = set<sl>;
using vvi = vector<vi>;
using vvb = vector<vb>;
using vvl = vector<vl>;
using pii = pair<int,int>;
using pll = pair<ll,ll>;
using vs = vector<string>;
using vpi = vector<pii>;
using vpl = vector<pll>;
using vvpl = vector<vpl>;
#define umap unordered_map
#define eb emplace_back
#define pb push_back
#define lb lower_bound
#define ub upper_bound
#define mp make_pair
#define ff first
#define ss second
#define ar array
inline void yn(bool b)
{
    if(b==true)
        cout<<"Yes\n";
    else
        cout<<"No\n";
}
  inline void fastio() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  cout.tie(nullptr);
}

ll Mod = 1e9+7;
inline bool hasbit(ll nr, ll pos)
{
    return (nr&(1ll<<pos));
}

const string TASK("lca");
ifstream fin(TASK + ".in");
ofstream fout(TASK + ".out");
#define cin fin
#define cout fout
const ll Inf = 0x3f3f3f3f;
bool testCase = false;
const ll Nmax=2e5+10;
const ll LOG=18;
ll n,m,first[Nmax],cnt=0,p[Nmax],h[Nmax],rmq[LOG][Nmax];
vl G[Nmax];
void dfs(int nod,int hi)
{
  cnt++;
  h[cnt] = hi;
  p[cnt] = nod;
  if(first[nod]==0)
    first[nod] = cnt;
  for(auto c:G[nod])
    {dfs(c,hi+1);
    cnt++;
    p[cnt] = nod;
    h[cnt] = hi;}
}

void solve_testcase()
{
  cin>>n>>m;
  for(int i=2;i<=n;i++)
  {
    ll x;
    cin>>x;
    G[x].eb(i);
  }
  dfs(1,0);
  for(int i=1;i<=cnt;i++)
    rmq[0][i] = i;
  for(int l=1;l<LOG;l++)
  {
    for(int i=1;i+(1<<l)<=cnt;i++)
    {
      ll p1 = rmq[l-1][i];
      ll p2 = rmq[l-1][i+(1<<(l-1))];
      if(h[p1]<=h[p2])
        rmq[l][i] = p1;
      else rmq[l][i] = p2;
    }
  }
  for(int i=1;i<=m;i++)
  {
    ll x,y;
    cin>>x>>y;
    x = first[x];
    y = first[y];
    if(x>y)swap(x,y);
    ll lg = 0;
    while(x+(1<<(lg+1))<=y)
      lg++;
    ll p1 = rmq[lg][x];
    ll p2 = rmq[lg][y-(1<<lg)+1];
    if(h[p1] <= h[p2])
      cout<<p[p1]<<'\n';
    else cout<<p[p2]<<'\n';
  }
  /*for(int i=1;i<=cnt;i++)
    cout<<p[i]<<" ";
  cout<<'\n';
  for(int i=1;i<=cnt;i++)
    cout<<h[i]<<" ";*/
}

void pregenerate()
{

}

/// Check for interruption of input!!
/// a+b=a^b+2*(a&b)
int main() {
    fastio();
    pregenerate();
    ll t=1;
    if (testCase) cin >> t;
    while (t--)
    {   //cout<<t<<endl;
        solve_testcase();
    }
    return 0;
}