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#include <bits/stdc++.h>
using namespace std;
#define LMAX 100005
vector<int> G[LMAX];
int n,T[LMAX][20];
int Niv[LMAX];
void dfs(int nod,int niv){
Niv[nod]=niv;
for(auto it : G[nod])
dfs(it,niv+1);
}
void precalc(){
for(int j=1;(1<<j)<=n;++j)
for(int i=1;i<=n;++i)
T[i][j]=T[T[i][j-1]][j-1];
}
int lca(int a,int b){
if(Niv[a]>Niv[b])
swap(a,b);
int log2_a=0,log2_b=0;
for(;(1<<log2_a)<Niv[a];++log2_a);
for(;(1<<log2_b)<Niv[b];++log2_b);
for(;log2_b>=0;--log2_b)
if(Niv[b]-(1<<log2_b)>=Niv[a])
b=T[b][log2_b];
if(a==b)
return a;
for(;log2_a>=0;--log2_a)
if(T[a][log2_a]!=0&&T[a][log2_a]!=T[b][log2_a]){
a=T[a][log2_a];
b=T[b][log2_a];
}
return T[a][0];
}
#define BUFF_SIZE (1<<12)
char buff[BUFF_SIZE];
int poz=BUFF_SIZE;
char GetChar(){
if(poz==BUFF_SIZE){
fread(buff,1,BUFF_SIZE,stdin);
poz=0;
}
return buff[poz++];
}
int GetInt(){
int n=0;
char c;
do{
c=GetChar();
}while(!isdigit(c));
do{
n=n*10+c-'0';
c=GetChar();
}while(isdigit(c));
return n;
}
int main(){
freopen("lca.in","r",stdin);
freopen("lca.out","w",stdout);
int q;
n=GetInt();
q=GetInt();
for(int i=2;i<=n;++i){
T[i][0]=GetInt();
G[T[i][0]].push_back(i);
}
dfs(1,0);
precalc();
while(q--){
int x,y;
x=GetInt();
y=GetInt();
printf("%d\n",lca(x,y));
}
return 0;
}