#include<bits/stdc++.h>
using namespace std;
FILE *f=fopen("lca.in","r");
FILE *g=fopen("lca.out","w");
const int NMAX = 100004;
int N,M,Tata[NMAX],Nivel[NMAX],Rad=1;
vector<int>G[NMAX]; /// lista de adiacenta a grafului
bitset<NMAX>viz;
void Read()
{
    fscanf(f,"%d%d",&N,&M);
    for(int i=2; i<=N; i++)
    {
        fscanf(f,"%d",&Tata[i]);
        G[i].push_back(Tata[i]);
        G[Tata[i]].push_back(i);
    }
}
void Dfs(int nodCurent,int nivel)
{
    viz[nodCurent]=true;
    Nivel[nodCurent]=nivel;
    for(int nodVecin:G[nodCurent])
        if(!viz[nodVecin])Dfs(nodVecin,nivel+1);
}
int LCA(int x,int y)
{
    while(1)
    {
        if(x==y)return x;
        if(Tata[x]==y)return y;
        if(Tata[y]==x)return x;
        if(Tata[x]==Tata[y])return Tata[x];

        if(Nivel[x]==Nivel[y])
            x=Tata[x],y=Tata[y];
        else if(Nivel[x]>Nivel[y])
            x=Tata[x];
        else y=Tata[y];
    }
}
void Solve()
{
    Dfs(Rad,0);
    for(int m=1;m<=M;m++)
    {
        int x,y;fscanf(f,"%d%d",&x,&y);
        fprintf(g,"%d\n",LCA(x,y));
    }
}
int main()
{
    Read();
    Solve();
    fclose(f);
    fclose(g);
    return 0;
}