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#include <bits/stdc++.h>
#define pii pair<int,int>
using namespace std;
ifstream f("lca.in");
ofstream g("lca.out");
int n,q,x,k,viz[100200],nivel[100200],first[100200],node[400200],rmq[20][400200];
vector <int> edges[100200];
void euler(int x){
viz[x]=1;
node[++k]=x;
for(auto y:edges[x])
if(viz[y]==0)
nivel[y]=nivel[x]+1, euler(y), node[++k]=x;
}
void rmqprecalc()
{
for(int i=1; i<=k; i++)
rmq[0][i]=i;
for(int l=1; (1<<l)<=k; l++)
for(int i=1; i<=k-(1<<l)+1; i++)
{
int j=i+(1<<(l-1));
if(nivel[node[rmq[l-1][i]]]<=nivel[node[rmq[l-1][j]]])
rmq[l][i]=rmq[l-1][i];
else
rmq[l][i]=rmq[l-1][j];
}
}
int32_t main()
{
f>>n>>q;
for(int i=2; i<=n; i++)
f>>x, edges[x].push_back(i);
euler(1);
rmqprecalc();
for(int i=1; i<=k; i++)
cout<<i<<' ';
for(int i=1; i<=k; i++)
if(first[node[i]]==0)
first[node[i]]=i;
for(int i=1; i<=q; i++)
{
int x,y;
f>>x>>y;
x=first[x], y=first[y];
if(x>y)
swap(x,y);
int l=log2(y-x+1);
if(nivel[node[rmq[l][x]]]<nivel[node[rmq[l][y-(1<<l)+1]]])
g<<node[rmq[l][x]]<<'\n';
else
g<<node[rmq[l][y-(1<<l)+1]]<<'\n';
}
return 0;
}