#include <cstdio>
#include <vector>
#include <algorithm>

using namespace std;

vector<int>v[100010];
int v1[200010],niv[200010],first[100010],sol[20][100010],lg[200010],n,m,i,j,x,y,nr,lim,a;

void dfs(int nod,int lev)
{
    vector<int>::iterator it;
    v1[++nr]=nod;
    niv[nr]=lev;
    first[nod]=nr;
    for(it=v[nod].begin();it!=v[nod].end();it++)
    {
        dfs(*it,lev+1);
        v1[++nr]=nod;
        niv[nr]=lev;
    }
}

int main()
{
    freopen("lca.in", "r", stdin);
    freopen("lca.out", "w", stdout);
    scanf("%d%d",&n,&m);
    for(i=2;i<=n;i++)
    {
        scanf("%d",&x);
        v[x].push_back(i);
    }
    dfs(1,0);
    for(i=2;i<=nr;i++) lg[i]=lg[i/2]+1;
    for(i=1;i<=nr;i++) sol[0][i]=i;
    for(i=1,x=2;x<=nr;i++,x<<=1)
    {
        lim=nr-x+1;
        for(j=1;j<=lim;j++)
            if(niv[sol[i-1][j]]<niv[sol[i-1][j+x/2]]) sol[i][j]=sol[i-1][j];
            else sol[i][j]=sol[i-1][j+x/2];
    }
    for(i=1;i<=m;i++)
    {
        scanf("%d%d",&x,&y);
        x=first[x];
        y=first[y];
        if(x>y) swap(x,y);
        lim=lg[y-x+1];
        if(niv[sol[lim][x]]<niv[sol[lim][y-(1<<lim)+1]]) a=sol[lim][x];
        else a=sol[lim][y-(1<<lim)+1];
        printf("%d\n",v1[a]);
    }
    return 0;
}