#include <iostream>
#include <vector>
#include <stdio.h>
#define NMax 100005
#define LGMax 22
using namespace std;
int RMQ[LGMax][NMax],L[NMax],H[NMax],Lg[NMax],First[NMax];
int K,N,M,x;
vector<int> Graf[NMax];

void Read()
{
    freopen("lca.in","r",stdin);
    scanf("%d%d",&N,&M);
    for(int i=2;i<=N;i++)
    {
        scanf("%d",&x);
        Graf[x].push_back(i);
    }
}

void DFS(int nod,int lev)
{
    H[++K]=nod;
    L[K]=lev;
    First[nod]=K;

    for(vector<int>::iterator it=Graf[nod].begin();it!=Graf[nod].end();it++)
    {
        DFS(*it,lev+1);
        H[++K]=nod;
        L[K]=lev;
    }
}

void Rmq()
{
    for(int i=2;i<=K;i++)
        Lg[i]=Lg[i>>1]+1;
    for(int i=1;i<=K;i++)
        RMQ[0][i]=i;

    for(int i=1;(1<<i)<K;i++)
        for(int j=1;j<=K-(1<<i);j++)
        {
            int l=1<<(i-1);
            RMQ[i][j]=RMQ[i-1][j];
            if(L[RMQ[i-1][j+1]]<L[RMQ[i][j]])
                RMQ[i][j]=RMQ[i-1][j+1];
        }
}

int LCA(int x,int y)
{
    int dif,l,sol,sh;
    int a=First[x];
    int b=First[y];
    if(a>b)
        swap(a,b);
    dif=b-a+1;
    l=Lg[dif];
    sol=RMQ[l][a];
    sh=dif-(1<<l);
    if(L[sol]>L[RMQ[l][a+sh]])
        sol=RMQ[l][a+sh];
    return H[sol];
}

int main()
{
    Read();
    DFS(1,0);
    Rmq();
    freopen("lca.out","w",stdout);
    while(M--)
    {
        int x,y;
        scanf("%d%d",&x,&y);
        printf("%d\n",LCA(x,y));
    }
}