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#include <iostream>
#include <fstream>
#include <vector>
using namespace std;
ifstream f ("lca.in");
ofstream g ("lca.out");
const int SIZE = 100001;
const int LOG = 17;
int n, q, cnt;
int node[2 * SIZE], first[SIZE], logarithm[SIZE];
int st[SIZE][LOG + 1];
vector <int> G[SIZE];
void Read()
{
f >> n >> q;
for (int i = 2; i <= n; i++)
{
int x;
f >> x;
G[x].push_back(i);
}
}
void MarkNodeAsVisited(int currentNode)
{
cnt++;
node[cnt] = currentNode;
if (first[currentNode] == 0)
{
first[currentNode] = cnt;
}
}
void DFS(int start)
{
MarkNodeAsVisited(start);
for (unsigned int i = 0; i < G[start].size(); i++)
{
int neighbour = G[start][i];
DFS(neighbour);
MarkNodeAsVisited(start);
}
}
void ProcessSparseTable()
{
for (int i = 1; i <= cnt; i++)
{
st[i][0] = node[i];
}
for (int j = 1; j <= LOG; j++)
{
for (int i = 1; i - 1 + (1 << j) <= cnt; i++)
{
st[i][j] = min(st[i][j-1], st[i + (1 << (j-1))][j-1]);
}
}
logarithm[1] = 0;
for (int i = 2; i <= SIZE; i++)
{
logarithm[i] = logarithm[i/2] + 1;
}
}
int LCA(int x, int y)
{
int left = min(first[x], first[y]);
int right = max(first[x], first[y]);
int length = right - left + 1;
int j = logarithm[length];
return min(st[left][j], st[right + 1 - (1 << j)][j]);
}
void ProcessQueries()
{
for (int i = 1; i <= q; i++)
{
int x, y;
f >> x >> y;
g << LCA(x, y) << "\n";
}
}
int main()
{
Read();
DFS(1);
ProcessSparseTable();
ProcessQueries();
}