#include<cstdio>
#include<vector>
#include<algorithm>
using namespace std;
const int NMAX = 100005;
int N,M,K,X,Y,A,B,DIF,LCA,P,p,i,j,RMQ[18][2*NMAX];
int Euler[2*NMAX],Level[2*NMAX],First[NMAX];
vector<int> V[NMAX];
void Read()
{
    freopen("lca.in","r",stdin);
    freopen("lca.out","w",stdout);
    scanf("%d%d",&N,&M);
    for(i=2;i<=N;i++)
    {
        scanf("%d",&X);
        V[X].push_back(i);
    }
}
void DFS(int X,int L)
{
    Euler[++K]=X; Level[K]=L;
    First[X]=K;
    for(vector<int>::iterator it=V[X].begin();it!=V[X].end();it++)
    {
        DFS(*it,L+1);
        Euler[++K]=X;
        Level[K]=L;
    }
}
void BuildRMQ()
{
    for(i=1;i<=K;i++) RMQ[0][i]=i;
    for(P=2,p=1,i=1;P<=K;P<<=1,p<<=1,i++)
        for(j=1;j+P<=K+1;j++)
        {
            RMQ[i][j]=RMQ[i-1][j];
            if(Level[RMQ[i-1][j+p]]<Level[RMQ[i][j]]) RMQ[i][j]=RMQ[i-1][j+p];
        }
}
void Query()
{
    for(;M;M--)
    {
        scanf("%d%d",&X,&Y);
        A=First[X]; B=First[Y];
        if(A>B) swap(A,B); DIF=B-A;
        for(i=0,P=1;P<=DIF;i++,P<<=1); P>>=1; i--;
        LCA=RMQ[i][A];
        if(Level[RMQ[i][B-P+1]]<Level[RMQ[i][A]]) LCA=RMQ[i][B-P+1];
        printf("%d\n",Euler[LCA]);
    }
}
int main()
{
    Read();
    DFS(1,0);
    BuildRMQ();
    Query();
    return 0;
}