#include <bits/stdc++.h>
using namespace std;
#define nmax 100000
#define lgmax 17
ifstream f("lca.in");
ofstream g("lca.out");

int n,niv[nmax+5],up[nmax+5][lgmax+1];
vector<int>gr[nmax+5];

void dfs(int nod,int tata){
    for(int i=1;i<=lgmax;++i)
        up[nod][i]=up[up[nod][i-1]][i-1];
    for(auto i:gr[nod])
        if(i!=tata){
            niv[i]=niv[nod]+1;
            up[i][0]=nod;
            dfs(i,nod);
        }
}

int lca(int a,int b){
    if(niv[a]<niv[b])swap(a,b);
    for(int i=lgmax;i>=0;--i)
        if(up[a][i] and niv[up[a][i]]>=niv[b])
        a=up[a][i];
    if(a==b)return a;
    for(int i=lgmax;i>=0;--i)
        if(up[a][i] and up[b][i] and up[a][i]!=up[b][i]){
            a=up[a][i];
            b=up[b][i];
        }
    return up[a][0];
}

int main()
{
    int n,m;
    f>>n>>m;
    for(int i=2;i<=n;++i)
    {
        int x;
        f>>x;
        gr[x].push_back(i);
        gr[i].push_back(x);
    }
    dfs(1,0);
    for(int i=1;i<=m;++i)
    {
        int a,b;
        f>>a>>b;
        g<<lca(a,b)<<"\n";
    }
}