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#include <bits/stdc++.h>
using namespace std;
const int nmax=1e5+3, lg=20;
int sparse[nmax][lg], depth[nmax];
vector <int> v[nmax];
void dfs(int nod)
{
for(auto i:v[nod])
{
sparse[i][0]=nod;
for(int j=1; j<lg; j++)
{
sparse[i][j]=sparse[sparse[i][j-1]][j-1];
}
depth[i]=depth[nod]+1;
dfs(i);
}
}
int lca(int x, int y)
{
if(depth[x]<depth[y]) swap(x, y);
int dif=depth[x]-depth[y];
for(int i=lg-1; i>=0; i--)
{
if((1<<i)&dif)
{
x=sparse[x][i];
}
}
if(x==y) return x;
for(int i=lg-1; i>=0; i--)
{
if(sparse[x][i]!=sparse[y][i])
{
x=sparse[x][i];
y=sparse[y][i];
}
}
return sparse[x][0];
}
int main()
{
ifstream cin("lca.in");
ofstream cout("lca.out");
int n, q, a, b, x;
cin>>n>>q;
for(int i=2; i<=n; i++)
{
cin>>x;
v[x].push_back(i);
}
dfs(1);
while(q--)
{
cin>>a>>b;
cout<<lca(a, b)<<'\n';
}
return 0;
}