#include <cstdio>
#include <cstring>
#include <algorithm>
#define MaxN 100005
#define MaxLog 17
using namespace std;

FILE *IN,*OUT;

int Father[MaxLog][MaxN],h[MaxN],N,M,X,Y;

int LCA(int a,int b)
{
    if(h[a]>h[b])
    {
        int i=MaxLog-1;
        while(i>=0)
        {
            if(h[Father[i][a]]>=h[b])
                a=Father[i][a];
            i--;
        }
    }
    else if(h[b]>h[a])
    {
        int i=MaxLog-1;
        while(i>=0)
        {
            if(h[Father[i][b]]>h[a])
                b=Father[i][b];
            i--;
        }
    }
    if(a==b)return a;
    else
    {
        int i=MaxLog-1;
        while(i>=0)
        {
            if(Father[i][a]!=Father[i][b])
                a=Father[i][a],b=Father[i][b];
            i--;
        }
    }
    return Father[0][a];
}

int main()
{
    IN=fopen("lca.in","r");
    OUT=fopen("lca.out","w");

    fscanf(IN,"%d %d ",&N,&M);
    Father[0][1]=-1;
    h[1]=1;
    for(int i=2;i<=N;i++)
    {
        fscanf(IN,"%d ",&Father[0][i]);
        h[i]=1+h[Father[0][i]];
    }
    for(int i=1;i<=N;i++)
    {
        for(int j=1;j<MaxLog;j++)
            Father[j][i]=Father[j-1][Father[j-1][i]];
    }
    for(int i=1;i<=M;i++)
    {
        fscanf(IN,"%d %d ",&X,&Y);
        fprintf(OUT,"%d\n",LCA(X,Y));
    }
    return 0;
}