#include <fstream>
#include <cstdio>
#include <vector>
using namespace std;
ofstream fout("lca.out");
const int NMax = 100000;
const int Size = 8192;
int N,M;
vector <int> G[NMax + 5];
int A[20][NMax + 5],Log2[NMax + 5];
int Use[NMax + 5],TT[NMax + 5],Level[NMax + 5];
char Buffer[Size + 5];
int Pos;

inline void ReadValue(int & Value)
{
	Value=0;
	while(Buffer[Pos]<'0' || Buffer[Pos]>'9')
		{
		    Pos++;
		    if(Pos == Size)
            {
                fread(Buffer, 1, Size, stdin);
                Pos=0;
            }
		}

	while(Buffer[Pos]>='0' && Buffer[Pos]<='9')
	{
		Value = Value*10 + Buffer[Pos] - '0';
		Pos++;
		if(Pos == Size)
        {
            fread(Buffer, 1, Size, stdin);
            Pos=0;
        }
	}
}


void Read()
{
    freopen("lca.in","r",stdin);
    //fin >> N >> M;
    ReadValue(N); ReadValue(M);
    for(int i = 2; i <= N; ++i)
    {
        //fin >> TT[i];
        ReadValue(TT[i]);
        G[TT[i]].push_back(i);
    }
}
void Precalculate()
{
    for(int i = 2; i <= N; ++i)
        Log2[i] = Log2[i/2] + 1;
    for(int i = 1;i<= N; ++i)
        A[0][i] = TT[i];
    for(int i = 1; (1<<i) <= N; ++i)
        for(int j = 1; j <= N; ++j)
            A[i][j] = A[i-1][A[i-1][j]];
}
void DFS(int Nod)
{
    Use[Nod] = 1;
    for(int i = 0; i < (int)G[Nod].size(); ++i)
    {
        int Vecin = G[Nod][i];
        if(!Use[Vecin])
            {
                Level[Vecin] = Level[Nod] + 1;
                DFS(Vecin);
            }
    }
}
void SolveandPrint()
{
    DFS(1);
    while(M--)
    {
        int x,y;
        //fin >> x >> y;
        ReadValue(x); ReadValue(y);
        if(Level[x]<Level[y])
            swap(x,y);

        while(Level[x] != Level[y])
            {
                int k = Log2[Level[y]-Level[x]];
                x = A[k][x];
            }
        if(x == y)
        {
            fout << x << "\n";
            return;
        }
        for(int k = Log2[Level[x]]; k >= 0; --k)
        {
            if(A[k][x] != A[k][y])
            {
                x = A[k][x];
                y = A[k][y];
            }
        }
        fout << TT[x] << "\n";

    }
}
int main()
{
    Read();
    Precalculate();
    SolveandPrint();
    return 0;
}