#include <bits/stdc++.h>
#define ll long long
#define en "\n"
#define pb push_back
#define mp make_pair
#define pii pair<ll,ll>
#define fi first
#define se second
#define rep(i, a, b) for(ll i = a; i <= b; ++i)
#define per(i, a, b) for(ll i = a; i >= b; --i)
#define kaizokuO ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL)
#define r0 return 0
#define all(v) v.begin(), v.end()
#define MAX(v) *max_element(all(v))
#define MIN(v) *min_element(all(v))
#define gcd(a,b) __gcd(a,b);
#define lcm(a,b) (a*b)/ __gcd(a, b)
#define bitt(x) __builtin_popcount(x)
#define fill1(arr, i, n) for(ll a = 0; a <= n; ++a) arr[a] = i;
#define fill2(arr, i, n, m) for(ll a = 0; a <= n; ++a) for(ll b = 0; b <= m; ++b) arr[a][b] = i;
#define flsh fflush(stdout)
#define ext exit(0)
#define inp freopen("input.txt","r",stdin)
#define outp freopen("output.txt","w",stdout)
using namespace std;
//const ll mod = 1e9 + 7;
const ll mod = 998244353;
//const ll mod = 26101991;
//const ll mod = 1e8;
//const ll mod = 1e9+9;
//const double pi = 3.14159265;
vector<ll> adj[1000003];
string w[1000003];
string dfs(ll node){
string a = "";
for(auto i : adj[node]){
if(i<0){
if(w[abs(i)].length()>a.length()) a = w[abs(i)];
else if (w[abs(i)].length()==a.length())a = max(a, w[abs(i)]);
} else {
string t = dfs(i);
if(t.length()>a.length()) a = t;
else if(t.length()==a.length())a = max(a,t);
}
}
return a+"0";
}
void solve(){
ll n; cin >> n;
ll idx = 1;
for(ll i = 1; i <= n; ++i){
ll x; cin >> x;
if(x < 0){
string t = "";
x = abs(x);
while(x){
t = to_string(x%2)+t;
x /= 2;
}
w[idx] = t;
adj[i].pb(-idx);
idx++;
} else {
adj[i].pb(x);
}
cin >> x;
if(x < 0){
string t = "";
x = abs(x);
while(x){
t = to_string(x%2)+t;
x /= 2;
}
w[idx] = t;
adj[i].pb(-idx);
idx++;
} else {
adj[i].pb(x);
}
}
cout << dfs(1) << en;
}
int main() {
kaizokuO;
ll t = 1; //cin >> t;
while(t--){
solve();
}
}
