#include "Ali.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<ll> vii;
typedef pair<ll,ll> pii;
#define F first
#define S second
#define all(v) v.begin(),v.end()
#define pb push_back
const int M=10001;
const ll inf=1e9+10;
vii adj[M];
ll id[M];
ll t=0;
ll n;
void dfs(ll x,ll pa){
id[x]=t++;
for(auto it:adj[x]){
if(it==pa)
continue;
dfs(it,x);
}
}
string res;
void ord(ll x,ll pa){
for(auto it:adj[x]){
if(it==pa)
continue;
res.pb('1');
ord(it,x);
}
if(pa>=0)
res.pb('0');
}
void Init(int N, std::vector<int> U, std::vector<int> V) {
n=N;
for(int i=0;i<n-1;i++)
adj[U[i]].pb(V[i]),adj[V[i]].pb(U[i]);
dfs(0,-1);
for(int i=0;i<n;i++)
SetID(i,id[i]);
}
std::string SendA(std::string S){
ord(0,-1);
return res;
}
#include "Benjamin.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<ll> vii;
typedef pair<ll,ll> pii;
#define F first
#define S second
#define all(v) v.begin(),v.end()
#define pb push_back
namespace {
const ll M=1e5;
const ll inf=1e18;
ll n,x,y,pa[M],dis[M];
vii adj[M];
void dfs(ll x,ll pa=-1,ll d=0){
dis[x]=d;
for(auto it:adj[x]){
if(it==pa)
continue;
dfs(it,x,d+1);
}
}
}
std::string SendB(int N, int X, int Y) {
n=N,x=X,y=Y;
string r;
for(int i=0;i<20;i++)
r.pb('0');
return r;
}
int Answer(std::string T) {
ll t=0;
ll cur=0;
for(auto it:T){
if(it=='1'){
pa[++t]=cur;
cur=t;
}
else{
cur=pa[cur];
}
}
for(int i=1;i<=t;i++)
adj[i].pb(pa[i]),adj[pa[i]].pb(i);
dfs(x);
return dis[y];
}
