#include "parks.h"
#include "bits/stdc++.h"
using namespace std;
#ifndef EVAL
#include "grader.cpp"
#endif
#define ar array
typedef long long ll;
const int N = 2e5 + 5;
vector<ar<int, 3>> edges[N];
int construct_roads(vector<int> x, vector<int> y) {
int n = x.size();
map<ar<int, 2>, int> ss, mm;
for(int i=0;i<n;i++){
ss[{x[i], y[i]}] = i;
}
vector<ar<int, 2>> e, p;
auto add = [&](int a, int b, int p1, int p2){
edges[a].push_back({b, p1, p2});
edges[b].push_back({a, p1, p2});
};
for(int i=0;i<n;i++){
if(ss.count({x[i] - 2, y[i]})){
int j = ss[{x[i] - 2, y[i]}];
e.push_back({i, j});
p.push_back({-1, -1});
int u = e.size() - 1;
if(mm.count({x[i] - 1, y[i] - 1})){
int v = mm[{x[i] - 1, y[i] - 1}];
add(u, v, x[i] - 1, y[i] - 1);
mm.erase({x[i] - 1, y[i] - 1});
} else {
mm[{x[i] - 1, y[i] - 1}] = u;
}
if(mm.count({x[i] - 1, y[i] + 1})){
int v = mm[{x[i] - 1, y[i] + 1}];
add(u, v, x[i] - 1, y[i] + 1);
mm.erase({x[i] - 1, y[i] + 1});
} else {
mm[{x[i] - 1, y[i] + 1}] = u;
}
}
if(ss.count({x[i], y[i] - 2})){
int j = ss[{x[i], y[i] - 2}];
e.push_back({i, j});
p.push_back({-1, -1});
int u = e.size() - 1;
if(mm.count({x[i] - 1, y[i] - 1})){
int v = mm[{x[i] - 1, y[i] - 1}];
add(u, v, x[i] - 1, y[i] - 1);
mm.erase({x[i] - 1, y[i] - 1});
} else {
mm[{x[i] - 1, y[i] - 1}] = u;
}
if(mm.count({x[i] + 1, y[i] - 1})){
int v = mm[{x[i] + 1, y[i] - 1}];
add(u, v, x[i] + 1, y[i] - 1);
mm.erase({x[i] + 1, y[i] - 1});
} else {
mm[{x[i] + 1, y[i] - 1}] = u;
}
}
}
int m = e.size();
if(m != n - 1) return 0;
assert(m == n - 1);
for(int i=0;i<m;i++){
assert((int)edges[i].size() <= 2);
}
for(auto [x, i] : mm){
p[i] = x;
assert((int)edges[i].size() < 2):
}
vector<int> used(m);
function<void(int)> dfs = [&](int i){
used[i] = 1;
for(auto [x, p1, p2] : edges[i]){
if(used[x]) continue;
p[x] = {p1, p2};
dfs(x);
}
};
for(int i=0;i<m;i++){
if(used[i]) continue;
if(p[i][0] == -1){
assert(edges[i].size() == 2);
p[i] = {edges[i].back()[1], edges[i].back()[2]};
edges[i].pop_back();
}
dfs(i);
}
vector<int> u(m), v(m), A(m), B(m);
for(int i=0;i<m;i++){
u[i] = e[i][0], v[i] = e[i][1];
A[i] = p[i][0], B[i] = p[i][1];
assert(~A[i] && ~B[i]);
}
build(u, v, A, B);
return 1;
}
Compilation message
parks.cpp: In function 'int construct_roads(std::vector<int>, std::vector<int>)':
parks.cpp:82:35: error: expected ';' before ':' token
82 | assert((int)edges[i].size() < 2):
| ^
