#include<stdio.h>
#include<vector>
#include<algorithm>
    
#define maxn 100005
#define pb push_back
#define mp make_pair
    
using namespace std;
    
FILE*f=fopen("lca.in","r");
FILE*g=fopen("lca.out","w");
    
int n,m,k,fictive,N,index,val,loc,a,b;
int viz[maxn],nivelnod[maxn],indT[maxn],height[maxn],lant[maxn],tata_lant[maxn];
int first[maxn],last[maxn],sigure;
double arb_prob[4*maxn],now,doubleval; int arb_sigure[4*maxn];
vector< pair< int,pair<int,double> > >G[maxn];
vector< pair< int,double> >up[maxn],down[maxn];
double sol;

void dfs ( int nod , int nivel ){
    viz[nod] = 1;
    nivelnod[nod] = nivel;
    first[nod] = ++index;
    height[nod] = 1;
	
	int heavy = 0;
    for ( vector< pair< int,pair<int,double> > >::iterator itt = G[nod].begin() ; itt != G[nod].end() ; ++itt ){
        int vecin = itt->first;
            
        if ( !viz[vecin] ){
            indT[vecin] = itt->second.first;
            dfs(vecin,nivel+1);
            height[nod] += height[vecin];
            tata_lant[lant[vecin]] = nod;
            if ( height[vecin] > height[heavy] ){
				heavy = vecin;
            }
        }
    }
	
	if ( height[nod] == 1 ){
		lant[nod] = ++lant[0];
	}
	else{
		lant[nod] = lant[heavy];
	}
	
    last[nod] = index;
}
    
inline int lca ( int x , int y ){

	while ( lant[x] != lant[y] ){
	
		if ( nivelnod[tata_lant[lant[x]]] >= nivelnod[tata_lant[lant[y]]] ){
			x = tata_lant[lant[x]];
		}
		else{
			y = tata_lant[lant[y]];
		}
	}
	
	if ( nivelnod[x] <= nivelnod[y] ){
		return x;
	}
	return y;
}
    
int main () {
        
    fscanf(f,"%d %d",&n,&m);
    int x,y;
    for ( int i = 2 ; i <= n ; ++i ){
        fscanf(f,"%d",&x);
        //if ( x == y )   continue ;
        G[x].pb(mp(i,mp(i,0)));
        G[i].pb(mp(x,mp(i,0)));
    }
        
    dfs(1,0);
        
	
    //DFS(1);
     
    //init_prob(1,1,n);
    //dfs_sol(1);
     
    //fprintf(g,"%lf\n",sol);
    tata_lant[lant[1]] = 0; nivelnod[0] = -1;
    for ( int i = 1 ; i <= m ; ++i ){
		fscanf(f,"%d %d",&x,&y);
		fprintf(g,"%d\n",lca(x,y));
    }
     
    fclose(f);
    fclose(g);
        
    return 0;
}