#include <bits/stdc++.h>
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");
int str[100100][20], L[100100], N;
vector <int> G[100100];
inline void dfs(int nod, int lvl)
{
    L[nod]=lvl;
    for(auto it: G[nod])
        dfs(it, lvl+1);
}

inline int lca(int nod1, int nod2)
{
    if(L[nod1]<L[nod2])
        swap(nod1,nod2);
    int log2_1=log2(nod1), log2_2=log2(nod2);
    if((1<<log2_1)!=nod1) log2_1++;
    if((1<<log2_2)!=nod1) log2_2++;
    for(int i=log2_1; i>=0; i--)
        if(L[nod1]-L[nod2]>=(1<<i))
            nod1=str[nod1][i];
    if(nod1==nod2)
        return nod1;
    for(int i=log2_2; i>=0; i--)
        if(str[nod1][i] &&str[nod1][i]!=str[nod2][i])
            nod1=str[nod1][i], nod2=str[nod2][i];
    return str[nod1][0];
}

int main()
{
    ios :: sync_with_stdio(false);
    fin.tie(0);
    int M,x,y;
    fin>>N>>M;
    for(int i=2; i<=N; ++i)
        fin>>str[i][0], G[str[i][0]].push_back(i);
    dfs(1,0);

    int lim=log2(N);
    for(int j=1; j<=lim+1; ++j)
        for(int i=1; i<=N; ++i)
            str[i][j]=str[str[i][j-1]][j-1];

    while(M--)
    {
        fin>>x>>y;
        fout<<lca(x,y)<<'\n';
    }
    return 0;
}