#include <fstream>
#include <vector>
using namespace std;

const int MAX_N = 100002;

int N, M, Nr;
int A[2*MAX_N][20], pos[MAX_N], E[2*MAX_N], P[2*MAX_N][20], val[2*MAX_N], log[2*MAX_N];
vector < int > v[MAX_N];

inline void DFS(int x, int niv) {
    E[++Nr] = x, val[Nr] = niv, pos[x] = Nr;
    for(size_t i = 0; i < v[x].size(); ++i) {
        int y = v[x][i];
        DFS(y, niv+1);
        E[++Nr] = x, val[Nr] = niv;
    }
}

inline void RMQ() {
    for(int i = 1; i <= Nr; ++i)
        A[i][0] = val[i], P[i][0] = i;
    for(int j = 1; (1 << j) <= Nr; ++j)
        for(int i = 1; i + (1 << j) - 1 <= Nr; ++i)
            if(A[i][j-1] < A[i+(1 << (j-1))][j-1])
                A[i][j] = A[i][j-1], P[i][j] = P[i][j-1];
            else A[i][j] = A[i+(1 << (j-1))][j-1], P[i][j] = P[i+(1 << (j-1))][j-1];
}

inline int Query(int x, int y) {
    x = pos[x], y = pos[y];
    if(x > y)
        swap(x, y);
    int k = log[y-x+1], t = 0;
    if(A[x][k] < A[y-(1 << k) + 1][k])
        t = P[x][k];
    else t = P[y-(1 << k) + 1][k];

    return E[t];
}

int main() {
    ifstream f("lca.in");
    ofstream g("lca.out");

    f >> N >> M;
    for(int i = 2, x; i <= N; ++i) {
        f >> x;
        v[x].push_back(i);
    }

    DFS(1, 0);
    for(int i = 2; i < 2*MAX_N; ++i)
        log[i] = log[i/2] + 1;
    RMQ();

    for(int i = 1, x, y; i <= M; ++i) {
        f >> x >> y;
        g << Query(x, y) << "\n";
    }

    f.close();
    g.close();

}