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#include <bits/stdc++.h>
#define N 100000 + 5
using namespace std;
ifstream f("lca.in");
ofstream g("lca.out");
int n, m, pos;
int t[N], heavy[N], seq[N], position[N], level[N], size[N];
vector<int> graf[N];
void read() {
f>>n>>m;
for(int i = 2;i <= n;++i) {
f>>t[i];
graf[t[i]].push_back(i);
graf[i].push_back(t[i]);
}
}
void dfs(int node, int parent) {
level[node] = level[parent] + 1;
size[node] = 1;
int maxim = 0;
for(const auto& vecin : graf[node]) {
if(vecin != t[node]) {
dfs(vecin, node);
size[node] += size[vecin];
if(maxim < size[vecin]) {
maxim = size[vecin];
heavy[node] = vecin;
}
}
}
}
void decompose(int node, int superior) {
position[node] = pos++;
seq[node] = superior;
if(heavy[node]) {
decompose(heavy[node], superior);
}
for(const auto& vecin : graf[node]) {
if(vecin != t[node] && vecin != heavy[node]) {
decompose(vecin, vecin);
}
}
}
int lca(int x, int y) {
while(seq[x] != seq[y]) {
if(position[seq[x]] < position[seq[y]]) {
int temp = x;
x = y;
y = temp;
}
x = t[seq[x]];
}
if(level[x] > level[y]) {
return y;
}
return x;
}
void solve() {
dfs(1, 0);
decompose(1, 1);
int x, y;
for(int i = 1;i <= m;++i) {
f>>x>>y;
g<<lca(x, y)<<'\n';
}
}
int main() {
read();
solve();
return 0;
}