#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

ifstream fin("lca.in");
ofstream fout("lca.out");
#define dim 100005
#define int long long
int t[dim],dp[dim][21],niv[dim];
vector<int> v[dim];
void dfs(int x,int p=0)
{
    niv[x]=niv[p]+1;
    for(auto y:v[x])
    {
        if(y==p)
            continue;
        dfs(y,x);
    }
}
void Niv(int &x,int &y)
{
    if(niv[x]<niv[y])
        swap(x,y);
    /// y e mai sus decat x
    int k=19;
    while(niv[x]>niv[y])
    {
        if(niv[x]-1LL*(1<<k)>=niv[y])
        {
            x=dp[x][k];
        }
        k--;
    }
}
int stramos(int x,int y)
{
    if(x==y)
        return x;
    int k=19,xn,yn;
    while(k>=0)
    {
        xn=dp[x][k];
        yn=dp[y][k];
        if(xn!=yn)
        {
            x=xn;
            y=yn;
        }
        k--;
    }
    return dp[x][0];
}

signed main()
{
    int n,m,x,i,k,y;
    fin>>n>>m;
    for(i=2;i<=n;i++)
    {
        fin>>x;
        v[i].push_back(x);
        v[x].push_back(i);
        dp[i][0]=x;
    }
    dfs(1);
    for(k=1;k<20;k++)
    {
        for(i=2;i<=n;i++)
        {
            dp[i][k]=dp[dp[i][k-1]][k-1];
        }
    }
    for(i=0;i<m;i++)
    {
        fin>>x>>y;
        if(niv[x]!=niv[y])
        {
            //cout<<x<<" "<<y<<" : ";
            Niv(x,y);
            //cout<<x<<" "<<y<<endl;
        }
        fout<<stramos(x,y)<<'\n';
    }
    return 0;
}