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#include<bits/stdc++.h>
using namespace std;
typedef int var;
#define MAXN 100005
var D[MAXN], PathP[MAXN], Heavy[MAXN], In[MAXN];
vector<var> G[MAXN];
void dfs(var node) {
Heavy[node] = 1;
In[node] = node;
var best = 0;
for(auto vec : G[node]) {
D[vec] = D[node] + 1;
dfs(vec);
Heavy[node] += Heavy[vec];
PathP[In[vec]] = node;
if(best < Heavy[vec]) {
best = Heavy[vec];
In[node] = In[vec];
}
}
}
var lca(var a, var b) {
while(In[a] != In[b])
if(D[PathP[In[a]]] > D[PathP[In[b]]])
a = PathP[In[a]];
else
b = PathP[In[b]];
if(D[a] < D[b])
return a;
return b;
}
#define DIM 100000
char buff[DIM];
var poz;
void Read(var &a) {
while(!isdigit(buff[poz]))
if(++poz == DIM)
cin.read(buff, DIM), poz=0;
a = 0;
while(isdigit(buff[poz])) {
a = a * 10 + buff[poz] - '0';
if(++poz == DIM)
cin.read(buff, DIM), poz=0;
}
}
int main() {
freopen("lca.in", "r", stdin);
freopen("lca.out", "w", stdout);
var n, m, p, a, b;
Read(n); Read(m);
for(var i=2; i<=n; i++) {
Read(p);
G[p].push_back(i);
}
D[1] = 1;
dfs(1);
PathP[In[1]] = 0;
while(m--) {
Read(a); Read(b);
cout<<lca(a, b)<<'\n';
}
return 0;
}