#include "parks.h"
#include <algorithm>
#include <bitset>
#include <cstdint>
#include <cstring>
#include <iostream>
#include <limits.h>
#include <math.h>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <vector>
//#define int long long
#define loop(X, N) for(int X = 0; X < (N); X++)
#define all(V) V.begin(), V.end()
#define rall(V) V.rbegin(), V.rend()
using namespace std;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int, int> ii;
typedef vector<ii> vii;
typedef vector<vector<ii>> vvii;
typedef vector<bool> vb;
typedef vector<vector<bool>> vvb;
int construct_roads(std::vector<int> x, std::vector<int> y) {
int n = x.size();
vector<pair<ii, int>> benches(n);
loop(i, n) {
benches[i].first.first = y[i];
benches[i].first.second = x[i];
benches[i].second = i;
}
sort(all(benches));
int diff = benches.back().first.first - benches[0].first.first;
if (diff / 2 + 1 != n)
return 0;
int m = n - 1;
vi u(m), v(m), a(m), b(m);
loop(i, n - 1) {
u[i] = benches[i].second;
v[i] = benches[i + 1].second;
a[i] = 3;
b[i] = benches[i].first.first + 1;
}
build(u, v, a, b);
return 1;
}
