#include <fstream>
#include <vector>
#include <set>


int findLCA(const std::vector<int>& parents, int x, int y, int root)
{

    std::set<int> visited;

    while(true)
    {
        if(x != -1)
        {
            const auto res = visited.insert(x);
            if(!res.second)
                return *res.first;
            x = parents[x-1];
        }
        if(y != -1)
        {
            const auto res = visited.insert(y);
            if(!res.second)
                return *res.first;
            y = parents[y-1];
        }
    }
}

int main()
{
    std::ifstream fin("lca.in");
    std::ofstream fout("lca.out");

    auto n=0, m=0, x=0, y=0, root = 1;
    fin>>n>>m;
    std::vector<int> parents;
    parents.push_back(-1); // primul nod este nodul radacina

    for(auto i=0; i < n-1; ++i)
    {
        fin>>x;
        parents.push_back(x);
    }

    for(auto i=0; i < m; ++i)
    {
        fin >> x >> y;
        fout << findLCA(parents, x, y, root) << '\n';
    }

    return 0;
}