#include<stdio.h>
#include<vector>
#include<cmath>
using namespace std;
#define nmax 100005
int n, m, i, x, y, h, dim;
int niv[nmax], t[nmax], t2[nmax];
vector <int> ma[nmax];

void citire()
{
    scanf("%ld %ld",&n,&m);
    for (i=2;i<=n;i++)
    {
        scanf("%ld",&t[i]);
        ma[t[i]].push_back(i);
    }
}

void dfs1(int x)
{
    vector <int> ::iterator it;
    niv[x]=niv[t[x]]+1;
    if (h<niv[x])
        h=niv[x];
    for (it=ma[x].begin();it!=ma[x].end();it++)
        dfs1(*it);
}

void dfs2(int x, int n1)
{
    vector <int> ::iterator it;
    t2[x]=n1;
    if (niv[x]%dim==1)
        n1=x;
    for (it=ma[x].begin();it!=ma[x].end();it++)
        dfs2(*it,n1);
}

void lca(int x, int y)
{
    while (t2[x]!=t2[y])
    {
        if (niv[x]>niv[y])
            x=t2[x];
        else
            y=t2[y];
    }
    while (x!=y)
    {
        if (niv[x]>niv[y])
            x=t[x];
        else
            y=t[y];
    }
    printf("%ld\n",x);
}

int main()
{
    freopen("lca.in","r",stdin);
    freopen("lca.out","w",stdout);
    citire();
    dfs1(1);
    dim=long(sqrt(h))+1;
    dfs2(1,1);
    for (i=1;i<=m;i++)
    {
        scanf("%ld %ld",&x,&y);
        lca(x,y);
    }
    return 0;
}