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#include<bits/stdc++.h>
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");
#define NMAX 100005
int n,q;
vector<int> sons[NMAX];
vector<int> tour;
int ind[NMAX];
vector<int> depth;
int rm[2*NMAX][20];
void dfs(int u,int d)
{
ind[u]=tour.size();
tour.push_back(u);
depth.push_back(d);
for(auto s:sons[u])
{
dfs(s,d+1);
tour.push_back(u);
depth.push_back(d);
}
}
int msb(int x)
{
int rez=0;
while(x>0)
{
rez++;
x>>=1;
}
return rez;
}
void precompute()
{
for(int i=0;i<2*n-1;i++)
rm[i][0]=i;
for(int j=1;(1<<j)<2*n-1;j++)
{
for(int i=0;i+(1<<j)-1<2*n-1;i++)
{
int r1=rm[i][j-1];
int r2=rm[i+(1<<(j-1))][j-1];
rm[i][j]=(depth[r1]<depth[r2])?r1:r2;
}
}
}
int rmq(int a,int b)
{
int lg=msb(b-a+1);
lg--;
int r1=rm[a][lg],r2=rm[b-(1<<lg)+1][lg];
return (depth[r1]<depth[r2])?r1:r2;
}
int lca(int a,int b)
{
a=ind[a];
b=ind[b];
int r=rmq(min(a,b),max(a,b));
return tour[r];
}
int main()
{
fin>>n>>q;
for(int i=2;i<=n;i++)
{
int dad;
fin>>dad;
sons[dad].push_back(i);
}
dfs(1,1);
// cout<<1<<endl;
precompute();
for(int i=0;i<q;i++)
{
int a,b;
fin>>a>>b;
fout<<lca(a,b)<<'\n';
}
return 0;
}