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#include <fstream>
#include<vector>
#define NMAX 100001
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");
int n,m,q,x,y;
int nivel[NMAX],tata[20][NMAX];
vector<int>v[NMAX];
void dfs(int nod,int niv)
{
nivel[nod]=niv;
for(int i=0;i<v[nod].size();i++)
{
int nod1=v[nod][i];
dfs(nod1,niv+1);
}
}
int lca(int x,int y)
{
if(nivel[x]<nivel[y])
swap(x,y);
int log1,log2;
for(log1=1; (1<<log1)<nivel[x]; log1++);
for(log2=1; (1<<log2)<nivel[y]; log2++);
for(int k=log1;k>=0;k--)
if(nivel[x]-(1<<k)>=nivel[y])
x=tata[k][x];
if(x==y)
return x;
for(int k=log2;k>=0;k--)
if(tata[k][x]&&tata[k][x]!=tata[k][y])
{
x=tata[k][x];
y=tata[k][y];
}
return tata[0][x];
}
int main()
{
fin>>n>>q;
for(int i=2;i<=n;i++)
{
fin>>tata[0][i];
v[tata[0][i]].push_back(i);
}
for(int k=1;(1<<k)<=n;k++)
for(int i=1;i<=n;i++)
tata[k][i]=tata[k-1][tata[k-1][i]];
dfs(1,0);
for(int i=1;i<=q;i++)
{
fin>>x>>y;
fout<<lca(x,y)<<"\n";
}
return 0;
}