#include <bits/stdc++.h>

using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");
int n,m;
int parent[100003];
int rmq[100003][18];
int depth[100003];
int calc(int nod)
{
    if (parent[nod]==0)
    {
        depth[nod]=1;
        return 1;
    }
    if (depth[nod]!=0) return depth[nod];
    return depth[nod]=1+calc(parent[nod]);
}
int lca(int x,int y)
{
    if (depth[x]<depth[y]) swap(x,y);
    int diff=depth[x]-depth[y];
    for (int i=16;i>=0;i--)
    {
        if (diff&(1<<i))
        {
            x=rmq[x][i];
        }
    }
    if (x==y) return x;
    for (int i=16;i>=0;i--)
    {
        if (rmq[x][i]!=rmq[y][i])
        {
            x=rmq[x][i];
            y=rmq[y][i];
        }
    }
    return rmq[x][0];
}
int main()
{
    fin>>n>>m;
    for (int i=2;i<=n;i++)
    {
        fin>>parent[i];
        rmq[i][0]=parent[i];
    }
    for (int j=1;j<=16;j++)
        for (int i=1;i<=n;i++)
            rmq[i][j]=rmq[rmq[i][j-1]][j-1];
    for (int i=1;i<=n;i++)
        if (depth[i]==0) calc(i);
    while (m--)
    {
        int x,y;
        fin>>x>>y;
        fout<<lca(x,y)<<'\n';
    }
    return 0;
}