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#include <bits/stdc++.h>
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");
const int NSIZE = 100000 + 10;
const int LOG = 17;
vector < int > g[NSIZE];
int d[NSIZE];
int pa[LOG][NSIZE];
int N , i , x , y;
void df(int node , int father)
{
d[node] = d[father] + 1;
pa[0][node] = father;
for (int i = 0 ; i < g[node].size() ; ++i)
{
int to = g[node][i];
if (to == father) continue;
df(to , node);
}
}
void DP()
{
for (int i = 1 ; i <= LOG ; ++i)
for (int j = 1 ; j <= N ; ++j)
pa[i][j] = pa[i - 1][pa[i - 1][j]];
}
int kanc(int n,int k)
{
for (int i = LOG ; i >= 0 ; --i)
if ( (1 << i) <= k)
{
k -= (1 << i);
n = pa[i][n];
}
return n;
}
int lca(int x , int y)
{
// x is deeper than y
if (d[x] < d[y]) swap(x , y);
int q = d[x] - d[y];
x = kanc(x , q);
if (x == y) return x;
//now x is at same level with y
for (int i = LOG ; i >= 0 ; --i)
if (pa[i][x] != pa[i][y])
{
x = pa[i][x];
y = pa[i][y];
}
return pa[0][x];
}
int main()
{
int Q;
fin >> N >> Q;
for (i = 2 ; i <= N ; ++i)
{
fin >> x;
g[i].push_back(x);
g[x].push_back(i);
}
df(1 , 0);
DP();
for (i = 1 ; i <= Q ; ++i)
{
fin >> x >> y;
fout << lca(x , y) << '\n';
}
return 0;
}