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#include <bits/stdc++.h>
int main() {
std::ifstream fin("lca.in");
std::ofstream fout("lca.out");
int n, queries;
std::vector<int64_t> v;
std::vector<int64_t> p;
fin >> n >> queries;
v.resize(n + 1);
p.resize(n + 1);
for (int i = 2; i <= n; i++) {
int x;
fin >> x;
v[i] = v[x] + 1;
p[i] = x;
}
for (int i = 0; i < queries; ++i) {
int x, y;
fin >> x >> y;
if (x == y) {
fout << x << "\n";
continue;
}
if (x == 1 || y == 1) {
fout << 1 << "\n";
continue;
}
while (x != y) {
if (p[x] < p[y]) {
y = p[y];
} else {
x = p[x];
}
}
fout << x << "\n";
}
fin.close();
fout.close();
return 0;
}