#include<cstdio>
#include<vector>
#include<cmath>
#include<algorithm>
#define NMAX 100007
#define LMAX 22
 
using namespace std;

FILE* in=fopen("lca.in", "r");
FILE* out=fopen("lca.out", "w");
int first[NMAX], E[NMAX << 2], H[NMAX << 2];
int RMQ[LMAX][NMAX << 2];
vector<int> v[NMAX];


int n, m;
void citire()
{
	fscanf(in, "%d%d", &n, &m);
	int tata;
	for(int nod=2; nod<=n; ++nod)
	{
		fscanf(in, "%d", &tata);
		v[tata].push_back(nod);
	}
}

int k;
void dfs(int nod=1, int niv=0)
{
	E[++k]=nod;
	H[k]=niv;
	first[nod]=k;
	for(int i=0; i<v[nod].size(); ++i)
	{
		dfs(v[nod][i], niv+1);
		E[++k]=nod;
		H[k]=niv;
	}
}

void rmq()
{
	int lg=log2(k);
	for(int i=1; i<=k; ++i) RMQ[0][i]=i;
	for(int i=1; i<=lg; ++i)
	{
		for(int j=1; j<=k-(1<<(i-1))+1; ++j)
		{
			if(H[RMQ[i-1][j]]<H[RMQ[i-1][j+(1<<(i-1))]])
				RMQ[i][j]=RMQ[i-1][j];
			else RMQ[i][j]=RMQ[i-1][j+(1<<(i-1))];
		}
	}
}

int lca(int x, int y)
{
	if(x>y) swap(x, y);
	int dif=y-x+1;
	int lg=log2(dif);
	int sol=RMQ[lg][x];
	int s=y-(1<<lg)+1;
	if(H[sol]>H[RMQ[lg][s]]) sol=RMQ[lg][s];
	return E[sol];
}

int 
main()
{
	citire();
	dfs();
	rmq();
	for(int i=1; i<=m; ++i)
	{
		int x, y;
		fscanf(in, "%d%d", &x, &y);
		fprintf(out, "%d\n", lca(first[x], first[y]));
	}	
}