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#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define all(a) (a).begin(), (a).end()
#define forn(i,a,b) for (int i = a; i <= b; i++)
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
#define rc(s) return cout<<s,0
#define rcc(s) cout<<s,exit(0)
#define er erase
#define in insert
#define pi pair <int, int>
# define sz(x) (int)((x).size())
//#define int long long
const int dx[] = {0, 1, 0, -1};
const int dy[] = {1, 0, -1, 0};
const ll inf = 0x3f3f3f3f3f3f3f;
const int N = 2e5 + 11;
ifstream in("lca.in");
ofstream out("lca.out");
int n,k,pr[N],depth[N],dp[N][25],node[N],t,m;
vector<int>v[N];
void dfs(int nod,int p,int d){
pr[nod] = p;
depth[nod] = d;
for(auto it: v[nod]){
if(it==p)continue;
dfs(it,nod,d+1);
}
}
int lca(int x,int y){
for(int j = 20; j >= 0; j--){
if(depth[x] - (1<<j) >= depth[y]){
x = dp[x][j];
}
}
if(x==y)return x;
for(int j = 20; j >= 0; j--){
if(dp[y][j] && dp[x][j]!=dp[y][j]){
x = dp[x][j];
y = dp[y][j];
}
}
return dp[x][0];
}
int32_t main(){
ios_base::sync_with_stdio(0); cin.tie(0); cerr.tie(0); cout.tie(0);
in>>n>>m;
for(int i = 2,x; i <= n; i++){
in>>x;
dp[0][i]=x;
v[x].pb(i);
}
dfs(1,0,1);
for(int i = 1; i <= n; i++){
dp[i][0] = pr[i];
}
for(int j = 1; j <= 20; j++){
for(int i = 1; i <= n; i++){
dp[i][j] = dp[dp[i][j-1]][j-1];
}
}
for(int jj = 1, x, y; jj <= m; jj++){
in>>x>>y;
if(depth[x]<depth[y])swap(x,y);
out<<lca(x,y)<<'\n';
}
return 0;
}