#include "parks.h"
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
struct dsu {
int n;
vector<int> p, s;
dsu(int n) : n(n), p(n), s(n, 1) {
iota(p.begin(), p.end(), 0);
}
int find(int x) {
return x == p[x] ? x : p[x] = find(p[x]);
}
int size(int x) {
return s[find(x)];
}
bool same(int x, int y) {
return find(x) == find(y);
}
bool unite(int x, int y) {
x = find(x);
y = find(y);
if (x == y) {
return 0;
}
if (s[x] > s[y]) {
swap(x, y);
}
p[x] = y;
s[y] += s[x];
return 1;
}
};
constexpr int A = 200000;
int construct_roads(vector<int> X, vector<int> Y) {
int N = X.size();
vector f(7, vector(A + 3, -1));
for (int i = 0; i < N; i++) {
f[X[i]][Y[i]] = i;
}
dsu uf(N);
vector<int> u, v, a, b, m(A + 1, -1), l(A + 1, -1), r(A + 1, -1);
for (int y = 2; y <= A; y += 2) {
for (int x = 2; x <= 6; x += 2) {
if (f[x][y] != -1 && f[x][y + 2] != -1) {
if (x == 4) {
m[y + 1] = u.size();
}
u.push_back(f[x][y]);
v.push_back(f[x][y + 2]);
a.push_back(x == 2 ? 1 : 7);
b.push_back(y + 1);
uf.unite(f[x][y], f[x][y + 2]);
}
if (x != 6 && f[x][y] != -1 && f[x + 2][y] != -1) {
if (x == 2 && l[y - 2] == -1) {
l[y] = u.size();
u.push_back(f[x][y]);
v.push_back(f[x + 2][y]);
a.push_back(3);
b.push_back(-1);
uf.unite(f[x][y], f[x + 2][y]);
}
if (x == 4 && r[y - 2] == -1) {
r[y] = u.size();
u.push_back(f[x][y]);
v.push_back(f[x + 2][y]);
a.push_back(5);
b.push_back(-1);
uf.unite(f[x][y], f[x + 2][y]);
}
}
}
}
}
if (uf.size(0) != N) {
return 0;
}
vector<int> f(A, -1), s(A, -1), t(A, -1);
for (int i = 1; i <= A; i++) {
if (i % 2 == 1 && m[i] != -1) {
if (s[i - 1] != 1) {
a[m[i]] = 3;
f[i] = 0;
} else {
assert(t[i - 1] != 1);
a[m[i]] = 5;
f[i] = 1;
}
}
if (i % 2 == 0) {
if (l[i] != -1) {
if (f[i - 1] == 0) {
b[l[i]] = i + 1;
s[i] = 1;
} else {
b[l[i]] = i - 1;
s[i] = 0;
}
}
if (r[i] != -1) {
if (f[i - 1] == 1) {
b[r[i]] = i + 1;
t[i] = 1;
} else {
b[r[i]] = i - 1;
t[i] = 0;
}
}
}
}
build(u, v, a, b);
return 1;
}
Compilation message
parks.cpp: In function 'int construct_roads(std::vector<int>, std::vector<int>)':
parks.cpp:75:5: warning: no return statement in function returning non-void [-Wreturn-type]
75 | }
| ^
parks.cpp: At global scope:
parks.cpp:76:5: error: expected unqualified-id before 'if'
76 | if (uf.size(0) != N) {
| ^~
parks.cpp:80:5: error: expected unqualified-id before 'for'
80 | for (int i = 1; i <= A; i++) {
| ^~~
parks.cpp:80:21: error: 'i' does not name a type
80 | for (int i = 1; i <= A; i++) {
| ^
parks.cpp:80:29: error: 'i' does not name a type
80 | for (int i = 1; i <= A; i++) {
| ^
parks.cpp:112:10: error: expected constructor, destructor, or type conversion before '(' token
112 | build(u, v, a, b);
| ^
parks.cpp:113:5: error: expected unqualified-id before 'return'
113 | return 1;
| ^~~~~~
parks.cpp:114:1: error: expected declaration before '}' token
114 | }
| ^
