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#include <fstream>
#include <vector>
#define nmax 100001
using namespace std;
ifstream cin("lca.in");
ofstream cout("lca.out");
int st[nmax],dr[nmax],n,m,rmq[nmax][18],k,x,y;
vector<int>v[nmax];
bool is_dad(int x,int y){
return st[x]<st[y]&&dr[y]<dr[x];
}
void dfs(int nod){
st[nod]=++k;
for(auto i:v[nod])
dfs(i);
dr[nod]=++k;
}
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[x][i]!=0&&!is_dad(rmq[x][i],y))
x=rmq[x][i];
return rmq[x][0];
}
int main()
{
cin>>n>>m;
for(int i=2;i<=n;i++){
cin>>rmq[i][0];
v[rmq[i][0]].push_back(i);
}
dfs(1);
for(int i=1;i<18;i++)
for(int j=1;j<=n;j++)
rmq[j][i]=rmq[rmq[j][i-1]][i-1];
while(m--){
cin>>x>>y;
cout<<lca(x,y)<<'\n';
}
return 0;
}