#include <fstream>
#include <vector>
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");
const int N=100001;
vector<int>H[N];
int apar[N],lev[100*N],nr[100*N],dp[25][100*N],lg[100*N];
int k;
void dfs(int x,int lvl)
{
    lev[++k]=lvl;//lev=>nivelul de pe pozitia k in repr euler;
    nr[k]=x;//nr=>nodul de pe pozitia k in reprz euler;
    apar[x]=k;//apar=>prima aparitie a nodului X in reprz euler;
    for(vector<int>::iterator it=H[x].begin();it!=H[x].end();it++)
    {
        dfs(*it,lvl+1);
        nr[++k]=x;
        lev[k]=lvl;
    }
}
void rmq()
{
    int i,j;
    for(i=2;i<=k;i++) lg[i]=lg[i>>1]+1;
    for(i=1;i<=k;i++) dp[0][i]=i;
    for(i=1;(1<<i)<k;i++)
    {
        for(j=1;j<=k-(1<<i);j++)
        {
            dp[i][j]=dp[i-1][j];
            if(lev[dp[i-1][j]]>lev[dp[i-1][j+(1<<(i-1))]]) dp[i][j]=dp[i-1][j+(1<<(i-1))];
        };
    }
}
int lca(int x, int y)
{
//LCA-ul nodurilor x si y va fi nodul cu nivel minim din secventa (First[x], First[y]) din reprezentarea Euler a arborelui
    int diff, l, sol, sh;
    int a = apar[x], b = apar[y];
    if(a > b) swap(a, b);
    diff = b - a + 1;
    l = lg[diff];
    sol = dp[l][a];
    sh = diff - (1 << l);
    if(lev[sol] > lev[dp[l][a + sh]])
        sol = dp[l][a + sh];
    return nr[sol];
}
int main()
{
    int n,m,i,a,b;
    fin>>n>>m;
    for(i=2;i<=n;i++)
    {
        fin>>a;
        H[a].push_back(i);
    }
    dfs(1,0);
    rmq();
    for(i=1;i<=m;i++)
    {
        fin>>a>>b;
        fout<<lca(a,b)<<"\n";
    }
}