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#include <fstream>
#include <vector>
#define nmax (int)(1e5+1)
using namespace std;
ifstream cin("lca.in");
ofstream cout("lca.out");
int rmq[18][nmax],n,q,x,y,st[nmax],dr[nmax],k;
vector<int>v[nmax];
void dfs(int nod){
st[nod]=++k;
for(auto i:v[nod])
dfs(i);
dr[nod]=++k;
}
bool is_dad(int x,int y){
return st[x]<=st[y]&&dr[y]<=dr[x];
}
int lca(int x,int y){
if(is_dad(x,y))
return x;
if(is_dad(y,x))
return y;
for(int i=17;i>=0;i--)
if(rmq[i][x]!=0&&!is_dad(rmq[i][x],y))
x=rmq[i][x];
return rmq[0][x];
}
int main()
{
cin>>n>>q;
for(int i=2;i<=n;i++){
cin>>rmq[0][i];
v[rmq[0][i]].push_back(i);
}
dfs(1);
for(int i=1;i<18;i++)
for(int j=1;j<=n;j++)
rmq[i][j]=rmq[i-1][rmq[i-1][j]];
while(q--){
cin>>x>>y;
cout<<lca(x,y)<<'\n';
}
return 0;
}