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# include <fstream>
# include <algorithm>
# include <vector>
# define ZEU 200
# define NR 100005
using namespace std;
ifstream f("lca.in");
ofstream g("lca.out");
vector <int> v[NR];
int i,j,n,m,x,y,Q;
int niv[NR], T[NR], T2[NR];
void DFS (int k, int tata, int nivel)
{
T2[k]=tata; niv[k]=nivel;
if (nivel%ZEU==0) tata=k;
for (int i=0; i<v[k].size(); ++i)
DFS (v[k][i], tata, nivel+1);
}
int main ()
{
f>>n>>Q;
for (i=2; i<=n; ++i)
{
f>>T[i];
v[T[i]].push_back(i);
}
DFS (1, 0, 0);
for (i=1; i<=Q; ++i)
{
f>>x>>y;
while (T2[x]!=T2[y])
{
if(niv[x] > niv[y]) x=T2[x];
else y=T2[y];
}
while(x != y)
{
if(niv[x] > niv[y]) x=T[x];
else y=T[y];
}
g<<x<<"\n";
}
return 0;
}