#include<cstdio>
#include<cmath>
#include<algorithm>
#include<vector>
#define NMax 100005
using namespace std;

vector <int> neib[NMax];
int first[NMax],eu[2*NMax],k,n;
int level[2*NMax],b[2*NMax][20];

void df_euler (int vertex, int lev)
{
    eu[++k]=vertex;
    level[k]=lev;
    first[vertex]=k;
    for (int i=0; i<neib[vertex].size(); i++)
    {
        df_euler(neib[vertex][i],lev+1);
        eu[++k]=vertex;
        level[k]=lev;
    }
}

void RMQ()
{
    int i,j;
    for (i=1; i<=k; i++)
        b[i][0]=i;
    for (j=1; (1<<j)<=k; j++)
        for (i=1; i+(1<<j)-1<=k; i++)
            if (level[b[i][j-1]] < level[b[i+(1<<(j-1))][j-1]])
                b[i][j]=b[i][j-1];
            else b[i][j]=b[i+(1<<(j-1))][j-1];
}

int LCA (int x, int y)
{
    int st=first[x],dr=first[y],sol,aux;
    if (st>dr) swap(st,dr);
    aux=log10(dr-st+1)/log10(2);
    if (level[b[st][aux]]<level[b[dr-(1<<aux)+1][aux]])
        sol=b[st][aux];
    else sol=b[dr-(1<<aux)+1][aux];
    return eu[sol];
}

int main ()
{
    int m,i,t,x,y;
    freopen("lca.in","r",stdin);
    freopen("lca.out","w",stdout);
    scanf("%d%d",&n,&m);
    for (i=2; i<=n; i++)
    {
        scanf("%d",&t);
        neib[t].push_back(i);
    }
    df_euler(1,0);
    RMQ();
    for (i=1; i<=m; i++)
    {
        scanf("%d%d",&x,&y);
        printf("%d\n",LCA(x,y));
    }
    return 0;
}