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#include <bits/stdc++.h>
using namespace std;
ifstream in("lca.in");
ofstream out("lca.out");
int n,m,x,y,jmp[100000][100],Lev[100011];
int logN;
vector<int>v[100011];
void dfs(int nod,int lev){
Lev[nod]=Lev[lev]+1;
jmp[nod][0]=lev;
for(int i=1;i<20;i++)
jmp[nod][i]=jmp[jmp[nod][i-1]][i-1];
for(unsigned int i=0;i<v[nod].size();i++){
int s=v[nod][i];
if(s==lev)continue;
dfs(s,nod);
}
}
int lca(int x,int y){
if(Lev[x]<Lev[y])
swap(x,y);
for(int k=20;k>=0;k--)
if(Lev[x]-(1<<k)>=Lev[y])
x=jmp[x][k];
if(x==y)return x;
for(int k=20;k>=0;k--)
if(jmp[x][k] && jmp[x][k] !=jmp[y][k]){
x=jmp[x][k];
y=jmp[y][k];
}
return jmp[x][0];
}
int main(){
in >>n>>m;
//logN=int(log(n));
for(int i=2;i<=n;i++){
in>>jmp[0][i];
v[jmp[0][i]].push_back(i);
}
dfs(1,0);
for(int i=1;i<=n;i++)
for(int k=1;(1<<k)<=n;k++)
jmp[i][k]=jmp[jmp[i][k-1]][k-1];
for(int oo=0;oo<m;oo++){
in >>x>>y;
out <<lca(x,y)<<"\n";
}
return 0;
}