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#include <fstream>
#include <vector>
using namespace std;
ifstream cin("lca.in");
ofstream cout("lca.out");
int n,m,nivel[100005],tata[100005];
vector<int>l[100005];
void dfs(int nod,int niv)
{
nivel[nod]=niv;
for(int i=0;i<l[nod].size();i++)
{
int vecin=l[nod][i];
dfs(vecin,niv+1);
}
}
int lca(int x,int y)
{
if(nivel[x]<nivel[y])
swap(x,y);
while(nivel[x]>nivel[y])
x=tata[x];
while(x!=y)
{
x=tata[x];
y=tata[y];
}
return x;
}
int main()
{
cin>>n>>m;
for(int i=2;i<=n;i++)
{
cin>>tata[i];
l[tata[i]].push_back(i);
}
dfs(1,1);
while(m--)
{
int x,y;
cin>>x>>y;
cout<<lca(x,y)<<'\n';
}
return 0;
}