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

class input {
private:
    FILE* fin;
    char* t;
    int sp;
    const int sz = 10000;

    char read()
    {
        if (sp == sz)
        {
            fread(t, 1, sz, fin);
            sp = 0;
            return t[sp++];
        }
        else
            return t[sp++];
    }
public:
    input(const char* name)
    {
        fin = fopen(name, "r");
        sp = sz;
        t = new char[sz]();
    }

    void close()
    {
        fclose(fin);
    }

    void open(const char* name)
    {
        fin = fopen(name, "r");
        sp = sz;
        t = new char[sz]();
    }

    input& operator >> (int& n)
    {
        char c = read();

        while (c == ' ' || c == '\n')
            c = read();

        n = 0;

        int sng = 1;

        if (c == '-')
            sng = -1, c = read();

        while (c != '\0' && isdigit(c))
            n = n * 10 + (c - '0'), c = read();

        n *= sng;

        return *this;
    }

    input& operator >> (char& s)
    {
        char c = read();

        while (c != '\0' && c == '\n')
            c = read();

        s = c;

        return *this;
    }

    input& operator >> (long long& n)
    {
        char c = read();

        while (c == ' ' || c == '\n')
            c = read();

        n = 0;

        int sng = 1;

        if (c == '-')
            sng = -1, c = read();

        while (c != '\0' && isdigit(c))
            n = n * 10 + (c - '0'), c = read();

        n *= sng;

        return *this;
    }

    void getline(string& s)
    {
        char c = read();
        s = "";

        while (c != '\0' && c != '\n')
            s += c, c = read();
    }

    input& operator >> (string& s)
    {
        char c;
        c = read();
        s = "";

        while (c == '\n' || c == ' ')
            c = read();

        while (c != '\n' && c != '\0' && c != ' ')
            s += c, c = read();

        return *this;
    }

    input& operator >> (char* s)
    {
        char c;
        c = read();
        int i = 0;

        while (c == '\n' || c == ' ')
            c = read();

        while (c != '\n' && c != '\0' && c != ' ')
            s[i++] = c, c = read();

        return *this;
    }
};
class output {
private:
    FILE* fout;
    char* t;
    int sp;
    const int sz = 10000;

    void write(char c)
    {
        if (sp == sz)
        {
            fwrite(t, 1, sz, fout);
            sp = 0;
            t[sp++] = c;
        }
        else
            t[sp++] = c;
    }

public:
    output(const char* name)
    {
        fout = fopen(name, "w");
        sp = 0;
        t = new char[sz]();
    }

    ~output()
    {
        fwrite(t, 1, sp, fout);
    }

    output& operator << (int n)
    {
        if (n < 0)
        {
            write('-');
            n *= -1;
        }
        if (n <= 9)
            write(char(n + '0'));
        else
        {
            (*this) << (n / 10);
            write(char(n % 10 + '0'));
        }

        return *this;
    }

    output& operator << (char c)
    {
        write(c);

        return *this;
    }

    output& operator << (const char* s)
    {
        int i = 0;

        while (s[i] != '\0')
            write(s[i++]);

        return *this;
    }

    output& operator << (long long n)
    {
        if (n < 0)
        {
            write('-');
            n *= -1;
        }
        if (n < 10)
            write(char(n + '0'));
        else
        {
            (*this) << (n / 10);
            write(char(n % 10 + '0'));
        }

        return *this;
    }

    output& operator << (string s)
    {
        for (auto i : s)
            write(i);

        return *this;
    }

    void precizion(double x, int nr)
    {
        int p = floor(x);

        *this << p;

        if (nr == 0)
            return;

        write('.');

        for (int i = 1; i <= nr; i++)
        {
            x -= floor(x);
            x *= 10;

            write(int(x) + '0');
        }
    }
};

input fin("lca.in");
output fout("lca.out");

int v[500001], n, q, k, first[100001];
vector<vector<int>> rmq((500001), vector<int>(20));
vector<vector<int>> g(100001);

void dfs(int nod)
{
    v[++k] = nod;
    first[nod] = k;

    for (auto i : g[nod])
    {
        dfs(i);
        v[++k] = nod;
    }
}

void RMQ()
{
    for (int i = 1; i <= k; i++)
        rmq[i][0] = v[i];

    for (int j = 1; (1 << j) <= k; j++)
        for (int i = 1; i + (1 << j) - 1 <= k; i++)
            rmq[i][j] = min(rmq[i][j - 1], rmq[i + (1 << (j - 1))][j - 1]);
}

int minim(int l, int r)
{
    int j = log2(r - l + 1);

    return min(rmq[l][j], rmq[r - (1 << j) + 1][j]);
}

int main()
{
    fin >> n >> q;

    for (int i = 2; i <= n; i++)
    {
        int x;
        fin >> x;

        g[x].push_back(i);
    }

    dfs(1);
    RMQ();

    for(int i = 1; i <= q; i++)
    {
        int x, y;
        fin >> x >> y;

        fout << minim(min(first[x], first[y]), max(first[x], first[y])) << '\n';
    }

    return 0;
}