#include <bits/stdc++.h>

using namespace std;

class InParser {
private:
    FILE *fin;
    char *buff;
    int sp;
    char read_ch() {
        ++sp;
        if (sp == 4096) {
            sp = 0;
            fread(buff, 1, 4096, fin);
        }
        return buff[sp];
    }

public:
    InParser(const char* nume) {
        fin = fopen(nume, "r");
        buff = new char[4096]();
        sp = 4095;
    }
    InParser& operator >> (int &n) {
        char c;
        while (!isdigit(c = read_ch()) && c != '-');
        int sgn = 1;
        if (c == '-') {
            n = 0;
            sgn = -1;
        } else {
            n = c - '0';
        }
        while (isdigit(c = read_ch())) {
            n = 10 * n + c - '0';
        }
        n *= sgn;
        return *this;
    }
};

class OutParser {
private:
    FILE *fout;
    char *buff;
    int sp;
    void write_ch(char ch) {
        if (sp == 50000) {
            fwrite(buff, 1, 50000, fout);
            sp = 0;
            buff[sp++] = ch;
        } else {
            buff[sp++] = ch;
        }
    }

public:
    OutParser(const char* name) {
        fout = fopen(name, "w");
        buff = new char[50000]();
        sp = 0;
    }
    ~OutParser() {
        fwrite(buff, 1, sp, fout);
        fclose(fout);
    }
    OutParser& operator << (int vu32) {
        if (vu32 <= 9) {
            write_ch(vu32 + '0');
        } else {
            (*this) << (vu32 / 10);
            write_ch(vu32 % 10 + '0');
        }
        return *this;
    }
    OutParser& operator << (char ch) {
        write_ch(ch);
        return *this;
    }
    OutParser& operator << (const char *ch) {
        while (*ch) {
            write_ch(*ch);
            ++ch;
        }
        return *this;
    }
};

InParser fin("lca.in");
OutParser fout("lca.out");

const int lg = 20;
vector < vector < int > > G, ancestor;
vector < int > level;

void dfs(int node, int parent) {
    ancestor[node][0] = parent;
    for(int i = 1; i <= lg; ++i)
        ancestor[node][i] = ancestor[ancestor[node][i - 1]][i - 1];
    for(int next : G[node])
        if(next != parent) {
            level[next] = level[node] + 1;
            dfs(next, node);
        }
}

int lca(int u, int v) {
    if(level[u] < level[v])
        swap(u, v);
    for(int i = lg; i >= 0; --i)
        if(level[u] - (1 << i) >= level[v])
            u = ancestor[u][i];
    if(u == v)
        return u;
    for(int i = lg; i >= 0; --i)
        if(ancestor[u][i] != ancestor[v][i]) {
            u = ancestor[u][i];
            v = ancestor[v][i];
        }
    return ancestor[u][0];
}

int main() {
    int N, Q;
    fin >> N >> Q;
    G.resize(N + 1);
    for(int i = 2; i <= N; ++i) {
        int parent;
        fin >> parent;
        G[parent].emplace_back(i);
    }
    ancestor = vector < vector < int > >(N + 1, vector < int >(lg + 1));
    level.resize(N + 1);
    dfs(1, 0);
    while(Q--) {
        int u, v;
        fin >> u >> v;
        fout << lca(u, v) << '\n';
    }
}