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#include <iostream>
#include <fstream>
#include <vector>
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");
const int nmax = 100000, lgmax = 18;
vector <int> g[nmax + 5];
int n, m, lev[nmax + 5], log2[nmax + 5], a[lgmax][nmax + 5];
void Read(){
fin >> n >> m;
for (int i = 2; i <= n; i++){
fin >> a[0][i];
g[a[0][i]].push_back(i);
}
}
void CalcLevel(int nod){
lev[nod] = lev[a[0][nod]] + 1;
for (auto i : g[nod])
CalcLevel(i);
}
void Precalc(){
CalcLevel(1);
for (int i = 2; i <= n; i++)
log2[i] = log2[i / 2] + 1;
for (int i = 1; i <= log2[n]; i++)
for (int j = 1; j <= n; j++)
a[i][j] = a[i - 1][a[i - 1][j]];
}
int LCA(int x, int y){
if (lev[x] > lev[y])
swap(x, y);
while (lev[x] != lev[y]){
int dif = lev[y] - lev[x];
y = a[log2[dif]][y];
}
if (x == y)
return x;
for (int i = log2[n]; i >= 0; i--)
if (a[i][x] != a[i][y]){
x = a[i][x];
y = a[i][y];
}
return a[0][x];
}
void Print(){
while(m--){
int x, y;
fin >> x >> y;
fout << LCA(x, y) << '\n';
}
}
int main(){
Read();
Precalc();
Print();
return 0;
}