#include <fstream>
#include <vector>
using namespace std;
ifstream cin ("lca.in");
ofstream cout ("lca.out");
int e[200005];
int d[200005];
int s;
int f[100005];
int lg[200005];
int rmq[20][200005];
int n,m;
vector<int> g[100005];
void dfs(int nod,int l)
{
    e[++s] = nod;
    d[s] = l;
    f[nod] = s;
    for(auto u:g[nod])
    {
        dfs(u,l+1);
        e[++s] = nod;
        d[s] = l;
    }
}
void build()
{
    for(int i=2;i<=s;i++)
        lg[i] = lg[i/2] + 1;
    for(int i=1;i<=s;i++)
        rmq[0][i] = i;
    for(int i=1;i<=lg[s];i++)
        for(int j=1;j+(1<<i)-1<=s;j++)
        {
            int val1 = rmq[i-1][j];
            int val2 = rmq[i-1][j + (1<<(i-1))];
            if(d[val1]<d[val2])
                rmq[i][j] = val1;
            else
                rmq[i][j] = val2;
        }
}
int lca(int x,int y)
{
    int rasp = 0;
    x = f[x];
    y = f[y];
    if(x>y)
        swap(x,y);
    int dist = y - x + 1;
    int p = lg[dist];
    int f1 = rmq[p][x];
    int f2 = rmq[p][y - (1<<p) + 1];
    if(d[f1] < d[f2])
        return e[f1];
    return e[f2];
}
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    cin >> n >> m;
    for(int i=2;i<=n;i++)
    {
        int t;
        cin >> t;
        g[t].push_back(i);
    }
    dfs(1,0);
    build();
    for(int i=1;i<=m;i++)
    {
        int x,y;
        cin >> x >> y;
        cout << lca(x,y) << '\n';
    }
    return 0;
}