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#include <vector>
#include <map>
#include <fstream>
int i = 0, root = 1;
const int lg = 40;
const int o = 200000 + 20;
int e[o], d[o], h[o], c[o][lg];
using namespace std;
class tree{
public:
map<int,vector<int>> N;
void euler(int& current,int dist,int& i){
e[i]=current;
d[i]=dist;
if (h[current] == -1)h[current] = i;
for (auto& k : N[current]){
++i;
euler(k,dist + 1,i);
++i;
e[i]=current;
d[i]=dist;
}
}
void preprocess(){
euler(root, 0,i);
rmq2();
}
void rmq2(){
int j, N = i;
for (i = 0; i < N; ++i)
c[i][0] = i;
for (j = 1; 1 << j <= N; ++j)
for (i = 0; i + (1 << j) - 1 < N; ++i)
if (d[c[i][j - 1]] < d[c[i + (1 << (j - 1))][j - 1]])
c[i][j] = c[i][j - 1];
else
c[i][j] = c[i + (1 << (j - 1))][j - 1];
}
int lca(int a, int b){
int p1=h[a], p2=h[b];
if (p2 < p1){
p1 ^= p2; p2 = p1^p2; p1 ^= p2;
}
int k = 0, pow = 1;
while (pow <= p2 - p1 + 1){ pow <<= 1; ++k; }
pow >>= 1;
--k;
int index = d[c[p1][k]] <= d[c[p2 - pow + 1][k]] ? c[p1][k] : c[p2 - pow + 1][k];
return e[index];
}
void add(int&a, int&b){
N[a].push_back(b);
}
};
int main(){
ifstream f ("lca.in");
ofstream g("lca.out");
int n, m,x;
std::fill_n(h, o, -1);
f >> n >> m;
tree t;
for (int i = 2; i <= n; ++i){
f >> x;
t.add(x, i);
}
t.preprocess();
for (int i = 0; i < m; ++i){
f >> n >> x;
g << t.lca(n, x) << "\n";
}
return 0;
}