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#include <bits/stdc++.h>
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");
vector<int>v[100010];
int rmq[200010][20],level[200010],euler[200010],first[100010],lg,k,n,i,j,x,q,a,b;
void dfs(int nod,int nivel)
{
euler[++lg]=nod;
rmq[lg][0]=lg;
level[lg]=nivel;
if(first[nod]==0)
first[nod]=lg;
for(auto it:v[nod])
{
dfs(it,nivel+1);
euler[++lg]=nod;
rmq[lg][0]=lg;
level[lg]=nivel;
}
}
int lca(int x,int y)
{
x=first[x];
y=first[y];
if(x>y)
swap(x,y);
k=floor(log2(y-x+1));
int ans;
if(level[rmq[x][k]]<level[rmq[y-(1<<k)+1][k]])
ans=rmq[x][k];
else ans=rmq[y-(1<<k)+1][k];
return euler[ans];
}
int main()
{
fin>>n>>q;
for(i=2;i<=n;i++)
{
fin>>x;
v[x].push_back(i);
}
dfs(1,0);
for(j=1;(1<<j)<=lg;j++)
for(i=1;i+(1<<j)-1<=lg;i++)
if(level[rmq[i][j-1]]<level[rmq[i+(1<<(j-1))][j-1]])
rmq[i][j]=rmq[i][j-1];
else rmq[i][j]=rmq[i+(1<<(j-1))][j-1];
while(q--)
{
fin>>a>>b;
fout<<lca(a,b)<<'\n';
}
return 0;
}