#include <bits/stdc++.h>
#define for0(i,n) for(int i=0; i<n; i++)
#define for1(i,n) for(int i=1; i<=n; i++)
#define pb push_back
#define mp make_pair
#define all(v) v.begin(), v.end()
#define V vector<int>
#define VP vector<pair<int, int> >
#define clr(A,x) memset(A, x, sizeof(A))
#define cpy(A,B) memcpy(A, B, sizeof(B))
#define g(stream, s) getline(stream, s)
#define FASTIO ios_base::sync_with_stdio(0)
typedef long long ll;
typedef unsigned long long ull;
using namespace std;

const int CHARMAX = (1 << 10);
const int INFINT = 2000000000;
const ll INFLL = (1LL << 62);

/*class InParsare
{
private:
    FILE *fin;
    char *buffer;
    size_t index_of_buffer;

    char read_character()
    {
        index_of_buffer++;
        if(index_of_buffer == CHARMAX)
        {
            fread(buffer, 1, CHARMAX, fin);
            index_of_buffer = 0;
        }
        return buffer[index_of_buffer];
    }

public:
    InParsare(const char *name)
    {
        fin = fopen(name, "r");
        buffer = new char[CHARMAX]();
        index_of_buffer = CHARMAX - 1;
    }

    template<class T>
    InParsare &operator >> (T &n)
    {
        char c;
        while(!isdigit(c = read_character()) && c != '-');

        int sgn = 1;
        if(c == '-')
        {
            n = 0;
            sgn = -1;
        }
        else n = c - '0';

        while(isdigit(c = read_character()))
            n = n * 10 + c - '0';
        n *= sgn;

        return *this;
    }
};

class OutParsare
{
private:
    FILE *fout;
    char *buffer;
    size_t index_of_buffer;

    void write_character(char character)
    {
        if(index_of_buffer == CHARMAX)
        {
            fwrite(buffer, 1, CHARMAX, fout);
            index_of_buffer = 0;
            buffer[index_of_buffer++] = character;
        }
        else buffer[index_of_buffer++] = character;
    }

public:

    OutParsare(const char *name)
    {
        fout = fopen(name, "w");
        buffer = new char[CHARMAX]();
        index_of_buffer = 0;
    }

    ~OutParsare()
    {
        fwrite(buffer, 1, index_of_buffer, fout);
        fclose(fout);
    }
    template<class T>
    OutParsare &operator << (T n)
    {
        if(typeid(T).name() == typeid(char).name())
        {
            write_character(n);
            return *this;
        }

        if(n <= 9)
            write_character(n + '0');
        else
        {
            (*this) << (n / 10);
            write_character(n % 10 + '0');
        }

        return *this;
    }

};*/

//InParsare fin("statiuni.in"); /// merg numai pt numere
//OutParsare fout("statiuni.out"); /// merg numai pt numere + caractere individuale, nu stringuri
ifstream fin("lca.in");
ofstream fout("lca.out");

const int NMAX = 1e5 + 5;

int n, q;
V arbore[NMAX];
int ssize, euler[2 * NMAX], level[2 * NMAX], first[NMAX];
int rmq[20][4 * NMAX], lg[2 * NMAX];

void dfs(int nod = 1, int l = 0)
{
    euler[++ssize] = nod;
    level[ssize] = l;
    first[nod] = ssize;

    for(auto i: arbore[nod])
    {
        dfs(i, l + 1);

        euler[++ssize] = nod;
        level[ssize] = l;
    }
}

void construct_rmq()
{
    rmq[0][1] = 1;
    for(int i = 2; i <= ssize; i++)
        lg[i] = lg[i / 2] + 1, rmq[0][i] = i;

    for(int i = 1; (1 << i) <= ssize; i++)
        for(int j = 1; j <= ssize - (1 << i); j++)
        {
            rmq[i][j] = rmq[i - 1][j];

            if(level[ rmq[i][j] ] > level[ rmq[i - 1][j + (1 << (i - 1))] ])
                rmq[i][j] = rmq[i - 1][j + (1 << (i - 1))];
        }
}

int lca(int a, int b)
{
    int l = min(first[a], first[b]), r = max(first[a], first[b]);

    int dist = r - l + 1;
    int sol = rmq[ lg[dist] ][l];
    if(level[sol] > level[ rmq[ lg[dist] ][l + dist - (1 << lg[dist])] ])
        sol = rmq[ lg[dist] ][l + dist - (1 << lg[dist])];

    return euler[sol];
}



int main()
{
    fin >> n >> q;
    for1(i, n - 1)
    {
        int a;
        fin >> a;
        arbore[a].pb(i + 1);
    }

    dfs();
    construct_rmq();

    while(q--)
    {
        int a, b;
        fin >> a >> b;
        fout << lca(a, b) << '\n';
    }

    return 0;
}