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

const int N = 1 + 1e5;

int T[N], son[N], head[N], depth[N], heavyDepth[N], n;
int start[N], stop[N], timp;
vector<int> tree[N];

int dfs(int x){
    start[x] = ++timp;

    int weight = 0, best = -1, val;
    for (auto it = tree[x].begin() ; it != tree[x].end() ; it++){
        depth[*it] = 1 + depth[x];
        val = dfs(*it);
        weight += val;
        if (best < val){
            best = val;
            son[x] = *it;
        }
    }
    stop[x] = ++timp;

    return weight;
}

void build(int x, int H, int D){
    heavyDepth[x] = D;
    head[x] = H;

    for (auto it = tree[x].begin() ; it != tree[x].end() ; it++)
        if ( son[x] != *it )
            build( *it, x, D + 1 );
        else
            build( *it, H, D );
}

inline int getNext(int x){
    return head[x] != x ? head[x] : head[ T[x] ];
}

inline int isAncestor(int T, int x){
    return start[T] <= start[x] && stop[x] <= stop[T];
}

int lca(int x, int y){
    if ( isAncestor(x, y) )
        return x;
    if ( isAncestor(y, x) )
        return y;
    return lca(head[x], head[y]);
/*
    while ( !isAncestor(x, y) && !isAncestor(y, x) ){
        x = head[x];
        y = head[y];
    }
    return isAncestor(x, y) ? x : y;
*/
}

int main(){
    int nrQ, x, y;
    ifstream in("lca.in");

    in >> n >> nrQ;
    for (int i = 2 ; i <= n ; i++){
        in >> T[i];
        tree[ T[i] ].push_back(i);
    }

    dfs(1);
    build(1, 0, 1);

    ofstream out("lca.out");

    while (nrQ--){
        in >> x >> y;
        out << lca(x, y) << '\n';
    }

    in.close();
    out.close();

    return 0;
}