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/// Binary Lifting
#include <fstream>
#include <vector>
using namespace std;
ifstream in ("lca.in");
ofstream out ("lca.out");
const int max_size = 1e5 + 1, rmax = 18;
int t[rmax][max_size], lvl[max_size], lg[max_size];
vector <int> mc[max_size];
void dfs (int nod, int par)
{
lvl[nod] = lvl[par] + 1;
t[0][nod] = par;
for (auto f : mc[nod])
{
dfs(f, nod);
}
}
int anc (int x, int ord)
{
int e = 0;
while (ord > 0)
{
if (ord % 2 == 1)
{
x = t[e][x];
}
ord /= 2;
e++;
}
return x;
}
int lca (int x, int y)
{
int e = lg[lvl[x]];
while (e >= 0)
{
if (t[e][x] != t[e][y])
{
x = t[e][x];
y = t[e][y];
}
e--;
}
return t[0][x];
}
int main ()
{
int n, q;
in >> n >> q;
for (int i = 2; i <= n; i++)
{
int x;
in >> x;
mc[x].push_back(i);
lg[i] = lg[i / 2] + 1;
}
dfs(1, 0);
for (int e = 1; e < rmax; e++)
{
for (int i = 1; i <= n; i++)
{
t[e][i] = t[e - 1][t[e - 1][i]];
}
}
while (q--)
{
int x, y;
in >> x >> y;
if (lvl[x] > lvl[y])
{
swap(x, y);
}
y = anc(y, lvl[y] - lvl[x]);
if (x == y)
{
out << x << '\n';
}
else
{
out << lca(x, y) << '\n';
}
}
in.close();
out.close();
return 0;
}