#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx,popcnt,sse4,abm")
#include <bits/stdc++.h>
using namespace std;
#ifndef WAIMAI
#include "parks.h"
#endif
#ifdef WAIMAI
#define debug(HEHE...) cout << "[" << #HEHE << "] : ", dout(HEHE)
void dout() {cout << '\n';}
template<typename T, typename...U>
void dout(T t, U...u) {cout << t << (sizeof...(u) ? ", " : ""), dout(u...);}
#else
#define debug(...) 7122
#endif
#define ll long long
#define Waimai ios::sync_with_stdio(false), cin.tie(0)
#define FOR(x,a,b) for (int x = a, I = b; x <= I; x++)
#define pb emplace_back
#define F first
#define S second
#ifdef WAIMAI
void build(vector<int> u, vector<int> v, vector<int> a, vector<int> b);
#endif
const int dx[4] = {-1, 0, 0, 1};
const int dy[4] = {0, -1, 1, 0};
const int SIZE = 2e5 + 5;
vector<int> adj[SIZE];
map<pair<int, int>, int> mp;
int deg[SIZE], pa[SIZE];
queue<int> q;
int construct_roads(vector<int> x, vector<int> y) {
int n = x.size();
FOR (i, 0, n - 1) mp[{x[i], y[i]}] = i;
FOR (i, 0, n - 1) FOR (j, 0, 3) {
int tx = x[i] + 2 * dx[j];
int ty = y[i] + 2 * dy[j];
if (mp.count({tx, ty})) adj[i].pb(mp[{tx, ty}]);
}
q.push(0);
fill(pa, pa + n, -1);
while (q.size()) {
int pos = q.front();
q.pop();
for (int np : adj[pos]) if (np != 0 && pa[np] == -1) {
pa[np] = pos;
deg[pos]++;
q.push(np);
}
}
FOR (i, 1, n - 1) if (pa[i] == -1) return 0;
FOR (i, 0, n - 1) if (!deg[i]) q.push(i);
vector<int> u, v, a, b;
set<pair<int, int>> s;
while (q.size()) {
int pos = q.front();
q.pop();
if (pos == 0) break;
int lx, ly, rx, ry;
tie(lx, ly) = make_pair(x[pos], y[pos]);
tie(rx, ry) = make_pair(x[pa[pos]], y[pa[pos]]);
u.pb(pos), v.pb(pa[pos]);
int mx = (lx + rx) / 2, my = (ly + ry) / 2;
vector<int> id(2);
if (lx == rx) id[0] = 0, id[1] = 3;
else id[0] = 1, id[1] = 2;
for (int i : id) {
int tx = mx + dx[i], ty = my + dy[i];
if (s.count({tx, ty})) continue;
a.pb(tx), b.pb(ty);
s.emplace(tx, ty);
break;
}
if (u.size() > a.size()) assert(0);
}
build(u, v, a, b);
return 1;
}
/*
in1
5
4 4
4 6
6 4
4 2
2 4
out1
1
4
0 2 5 5
0 1 3 5
3 0 5 3
4 0 3 3
in2
2
2 2
4 6
out2
0
*/
#ifdef WAIMAI
static void check(bool cond, string message) {
if (!cond) {
printf("%s\n", message.c_str());
fclose(stdout);
exit(0);
}
}
static int n;
static bool build_called;
static int m;
static vector<int> _u, _v, _a, _b;
void build(vector<int> u, vector<int> v, vector<int> a, vector<int> b) {
check(!build_called, "build is called more than once");
build_called = true;
m = u.size();
check(int(v.size()) == m, "u.size() != v.size()");
check(int(a.size()) == m, "u.size() != a.size()");
check(int(b.size()) == m, "u.size() != b.size()");
_u = u;
_v = v;
_a = a;
_b = b;
}
int main() {
assert(scanf("%d", &n) == 1);
vector<int> x(n), y(n);
for (int i = 0; i < n; i++) {
assert(scanf("%d%d", &x[i], &y[i]) == 2);
}
fclose(stdin);
build_called = false;
const int possible = construct_roads(x, y);
check(possible == 0 || possible == 1, "Invalid return value of construct_roads()");
if (possible == 1) {
check(build_called, "construct_roads() returned 1 without calling build()");
} else {
check(!build_called, "construct_roads() called build() but returned 0");
}
printf("%d\n", possible);
if (possible == 1) {
printf("%d\n", m);
for (int j = 0; j < m; j++) {
printf("%d %d %d %d\n", _u[j], _v[j], _a[j], _b[j]);
}
}
fclose(stdout);
return 0;
}
#endif
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 2 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 3 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 4 |
Incorrect |
4 ms |
5004 KB |
Given structure is not connected: There is no path between vertices 0 and 1 |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 2 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 3 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 4 |
Incorrect |
4 ms |
5004 KB |
Given structure is not connected: There is no path between vertices 0 and 1 |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 2 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 3 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 4 |
Incorrect |
4 ms |
5004 KB |
Given structure is not connected: There is no path between vertices 0 and 1 |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 2 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 3 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 4 |
Incorrect |
4 ms |
5004 KB |
Given structure is not connected: There is no path between vertices 0 and 1 |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 2 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 3 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 4 |
Incorrect |
4 ms |
5004 KB |
Given structure is not connected: There is no path between vertices 0 and 1 |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 2 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 3 |
Correct |
3 ms |
4948 KB |
Output is correct |
| 4 |
Incorrect |
4 ms |
5004 KB |
Given structure is not connected: There is no path between vertices 0 and 1 |
| 5 |
Halted |
0 ms |
0 KB |
- |
