#include <iostream>
#include <fstream>

using namespace std;

ifstream in("lca.in");
ofstream out("lca.out");
int n,m,a[100003],niv[100003];
int nv(int i)
{
    int c=0;
    while(a[i]!=0)
    {
        c++;
        i=a[i];
    }
    return c+1;
}
void parinte(int x,int y)
{
    while(niv[x]!=niv[y])
    {
        if(niv[x]>niv[y])
        {
            x=a[x];
        }
        else
            if(niv[x]<niv[y])
                y=a[y];
    }
    while(x!=y)
    {
        x=a[x];
        y=a[y];
    }
    out<<x<<'\n';
}
int main()
{
    in>>n>>m;
    int x,y;
    for(int i=2;i<=n;i++)
        in>>a[i];
    for(int i=1;i<=n;i++)
    {
        niv[i]=nv(i);
    }
    for(int i=0;i<m;i++)
    {
        in>>x>>y;
        parinte(x,y);
    }
    return 0;
}