#include <fstream>
#include <vector>

#define NMAX 100005
#define LOG 18

using namespace std;

ifstream fin("lca.in");
ofstream fout("lca.out");

int n, m;
int x, y;
vector<int> l[NMAX];
int dp[NMAX][LOG+2];
int tin[NMAX], tout[NMAX]; int timp;
bool f[NMAX];
int i, j, q;

int lca(int, int);
bool is_ancestor(int, int);
void dfs(int);

int main()
{
    fin >>n>>m;
    for (i = 2; i <= n; ++i)
    {
        fin >>dp[i][0];
        l[dp[i][0]].push_back(i);
    }

    for (j = 1; j <= LOG; ++j)
        for (i = 1; i <= n; ++i)
            dp[i][j] = dp[dp[i][j-1]][j-1];

    dfs(1);
    for (q = 1; q <= m; ++q)
    {
        fin >>x>>y;
        fout <<lca(x, y)<<'\n';
    }
    fout.close();
    return 0;
}

bool is_ancestor(int x, int y)
{
    if (!x || x == y) return 1;

    return (tin[x] < tin[y] && tout[x] > tout[y]);
}

int lca(int x, int y)
{
    if (is_ancestor(x, y)) return x;
    if (is_ancestor(y, x)) return y;

    int i;
    for (i = LOG; i >= 0; --i)
        if (!is_ancestor(dp[x][i], y))
            x = dp[x][i];

    return dp[x][0];
}

void dfs(int vf)
{
    int i;

    f[vf] = 1;
    tin[vf] = ++timp;

    for (auto vfnou: l[vf])
        if (!f[vfnou]) dfs(vfnou);

    tout[vf] = ++timp;
}