#include <bits/stdc++.h>
using namespace std;

ifstream f("LCA.in");
ofstream g("LCA.out");

#define LE 200666
#define pb push_back

int fap[LE],lap[LE],my_stack[LE],lev[LE],k;
vector<int> H[LE];
bool viz[LE];
int stack_size,random_up[LE],fth[LE];


void dfs(int nod)
{
	int N=H[nod].size(),i;
	viz[nod]=true;
	fap[nod]=++k;

	my_stack[++stack_size]=nod;
	int D=rand()%stack_size+1;
	random_up[nod]=my_stack[D];

	for(i=0;i<N;++i)
		if (viz[H[nod][i]]==false)
		{
			lev[H[nod][i]]=lev[nod]+1;
			dfs(H[nod][i]);
		}

	--stack_size;
	lap[nod]=k;
}

bool is_inside(int n1,int n2){
	return (fap[n2]>=fap[n1]&&fap[n2]<=lap[n1]);
}

int LCA(int n1,int n2)
{
	while (n1!=n2)
	{
		if (is_inside(random_up[n1],n2)==false) n1=random_up[n1];
		if (is_inside(random_up[n2],n1)==false) n2=random_up[n2];

		if (n1!=n2)
		{
			if (lev[n1]>=lev[n2]) n1=fth[n1];
			else n2=fth[n2];
		}
	}

	return n1;
}

int main()
{
    int n,i,m;
    f>>n>>m;

    for(i=2;i<=n;++i)
    {
    	f>>fth[i];
    	H[fth[i]].pb(i);
    	H[i].pb(fth[i]);
    }

    dfs(1);

    for(i=1;i<=m;++i)
    {
    	int xx,yy;
    	f>>xx>>yy;
    	g<<LCA(xx,yy)<<'\n';
    }



    return 0;
}