#include "tree.h"
#include<bits/stdc++.h>
#define Gc() getchar() 
#define Me(x,y) memset(x,y,sizeof(x))
#define Mc(x,y) memcpy(x,y,sizeof(x))
#define d(x,y) ((m)*(x-1)+(y))
#define R(n) (rnd()%(n)+1)
#define Pc(x) putchar(x)
#define LB lower_bound
#define UB upper_bound
#define PB push_back
#define fi first
#define se second
using ll=long long;using db=double;using lb=long db;using ui=unsigned;using ull=unsigned long long;using LL=__int128;
using namespace std;const int N=1e3+5,M=N*4+5,K=20,mod=1e4+7,Mod=mod-1;const db eps=1e-9;const int INF=1e9+7;mt19937 rnd(time(0));
int fa[N],w[N],d[N],F[N][11];vector<int> S[N];
int Ask(int x,int y){vector<int> Ts;Ts.PB(y);return ask(x,Ts);}
int LCA(int x,int y){
	d[x]<d[y]&&(swap(d[x],d[y]),0);while(d[x]^d[y]) x=F[x][__lg(d[x]-d[y])];
	if(x==y) return x;for(int i=10;~i;i--) F[x][i]^F[y][i]&&(x=F[x][i],y=F[y][i]);
	return F[x][0];
}
int Dt(int x,int y){return d[x]+d[y]-d[LCA(x,y)]*2;}
int Qry(int x,vector<int> y){
	int Ans=0;for(int i:y) Ans+=Dt(x,i);return Ans;
}
void Find(vector<int> S,vector<int> T){
	if(!T.size()) return;
	if(S.size()==1) {for(int i:T){fa[i]=S[0];F[i][0]=S[0];for(int j=1;F[i][j-1];j++) F[i][j]=F[F[i][j-1]][j-1];}return;}
	vector<int> S1,S2;shuffle(S.begin(),S.end(),rnd);
	int Ct=S.size();for(int i:S) if(Ct) Ct--,S1.PB(i);else S2.PB(i);
	int CC=0;map<int,int> f;
	for(int i:S) w[i]=Qry(i,S2),!f[w[i]]&&(f[w[i]]=++CC),w[i]=f[w[i]];
	for(int i:T) w[i]=f[ask(i,S2)-S2.size()];
	for(int i=1;i<=f.size();i++){
		vector<int> SS,TT;
		for(int j:S) if(w[j]==i) SS.PB(j);
		for(int j:T) if(w[j]==i) TT.PB(j);
		Find(SS,TT);
	}
}
void solver(int n, int A, int B){
	int Rt=R(n);int i;for(i=1;i<=n;i++) if(i^Rt) S[d[i]=Ask(Rt,i)].PB(i);
	S[0].PB(Rt);for(int i=1;i<=n;i++) if(S[i].size()) Find(S[i-1],S[i]);
	for(i=1;i<=n;i++) if(i^Rt) assert(fa[i]);
	for(i=1;i<=n;i++) if(i^Rt) answer(fa[i],i);
}