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#include <fstream>
using namespace std;
const int M=4000005;
const int N=100005;
const int L=17;
ifstream cin("lca.in");
ofstream cout("lca.out");
int vf[M], urm[M], lst[N], nr,ti[N], to[N], t[17][N], timp,n;
int adauga(int x, int y){
vf[++nr]=y;
urm[nr]=lst[x];
lst[x]=nr;
}
int lca(int x, int y){
/*if(ti[x]<=ti[y]&&to[y]<=to[x]){
return x;
}*/
int pas=L-1;
while(pas>=0){
int s=t[pas][x];
if(s!=0&&(ti[s]>ti[y]||to[y]>to[s])){
x=s;
}
pas--;
}
return t[0][x];
}
void dfs(int x){
ti[x]=++timp;
for(int p=lst[x];p!=0;p=urm[p]){
int y=vf[p];
if(ti[y]==0){
dfs(y);
t[0][y]=x;
}
}
to[x]=++timp;
}
int main()
{
int n,m,x,y;
cin>>n>>m;
for(int i=2;i<=n;i++){
cin>>x;
adauga(x,i);
}
dfs(1);
for(int i=1;i<L;i++){
for(int j=1;j<=n;j++){
t[i][j]=t[i-i][t[i-1][j]];
}
}
for(int i=1;i<=m;i++){
cin>>x>>y;
cout<<lca(x,y)<<'\n';
}
return 0;
}