oj.uz

Submission #827149

# Submission time Handle Problem Language Result Execution time Memory
827149 2023-08-16T09:18:41 Z ymm Fountain Parks (IOI21_parks) C++17
55 / 100
 3165 ms 76060 KB 
#include "parks.h"
#include <bits/stdc++.h>
#define Loop(x,l,r) for (ll x = (l); x < (r); ++x)
typedef long long ll;
typedef std::pair<int,int> pii;
using namespace std;

const int N = 200'010;

namespace dsu {
	int par[N];
	void init(int n) { memset(par, -1, sizeof(*par)*n); }
	int rt(int v) { return par[v] == -1? v: (par[v] = rt(par[v])); }
	bool unite(int v, int u) {
		v = rt(v);
		u = rt(u);
		if (v == u)
			return 0;
		par[u] = v;
		return 1;
	}
}

map<pii,int> pts;
vector<pii> edge;
vector<int> X, Y;
int n;

int get_pnt(int x, int y)
{
	auto it = pts.find(pii(x, y));
	return it == pts.end()? -1: it->second;
}

tuple<int,int,int,int> get_chair(int p1, int p2)
{
	int x1 = X[p1], y1 = Y[p1], x2 = X[p2], y2 = Y[p2];
	if (x1 == x2)
		return {x1-1, (y1+y2)/2, x1+1, (y1+y2)/2};
	else
		return {(x1+x2)/2, y1-1, (x1+x2)/2, y1+1};
}

namespace matching {
	int match[3*N];
	int par[3*N];
	vector<int> A[3*N];
	vector<pii> chairs;

	bool bfs(int s)
	{
		vector<int> q = {s}, q2;
		par[s] = -2;
		int vv;
		Loop (i,0,q.size()) {
			int v = q[i];
			//cerr << "bfs " << v << '\n';
			for (int u : A[v]) {
				if (par[u] != -1)
					continue;
				par[u] = v;
				q2.push_back(u);
				if (match[u] == -1) {
					vv = u;
					goto found;
				}
				int u2 = match[u];
				par[u2] = u;
				q.push_back(u2);
			}
		}
		return 0;
	found:
		while (vv != -2) {
			match[vv] = par[vv];
			match[par[vv]] = vv;
			vv = par[par[vv]];
		}
		for (int x : q2)
			par[x] = -1;
		return 1;
	}

	vector<pii> get_match(vector<pii> e) {
		int m = e.size();
		chairs.clear();
		Loop (i,0,m) {
			auto [p1, p2] = e[i];
			auto [x1, y1, x2, y2] = get_chair(p1, p2);
			chairs.emplace_back(x1, y1);
			chairs.emplace_back(x2, y2);
		}
		sort(chairs.begin(), chairs.end());
		chairs.resize(unique(chairs.begin(), chairs.end()) - chairs.begin());
		//for (auto [x, y] : chairs)
		//	cerr << x << ' ' << y << '\n';
		Loop (i,0,m+chairs.size()) {
			A[i].clear();
			match[i] = -1;
			par[i] = -1;
		}
		Loop (i,0,m) {
			auto [p1, p2] = e[i];
			auto [x1, y1, x2, y2] = get_chair(p1, p2);
			int c1 = lower_bound(chairs.begin(), chairs.end(), pii(x1, y1)) - chairs.begin();
			int c2 = lower_bound(chairs.begin(), chairs.end(), pii(x2, y2)) - chairs.begin();
			A[i].push_back(m+c1);
			A[i].push_back(m+c2);
			A[m+c1].push_back(i);
			A[m+c2].push_back(i);
		}
		Loop (i,0,m) {
			//cerr << "try " << i << '\n';
			if (!bfs(i))
				return {};
			//Loop (i,0,m+chairs.size())
			//	cerr << match[i] << ' ';
			//cerr << '\n';
		}
		//cerr << "all good!\n";
		vector<pii> ans;
		Loop (i,0,m) {
			int c = match[i]-m;
			ans.emplace_back(chairs[c].first, chairs[c].second);
		}
		return ans;
	}
}

void make_edges()
{
	Loop (i,0,n) {
		int x = X[i];
		int y = Y[i];
		if ((x+y)%2 == 0)
			continue;
		int p1 = get_pnt(x+2, y);
		int p2 = get_pnt(x, y+2);
		if (p1 != -1)
			edge.push_back({i, p1});
		if (p2 != -1)
			edge.push_back({i, p2});
	}
	Loop (i,0,n) {
		int x = X[i];
		int y = Y[i];
		if ((x+y)%2 == 1)
			continue;
		int p1 = get_pnt(x+2, y);
		int p2 = get_pnt(x, y+2);
		if (p1 != -1)
			edge.push_back({i, p1});
		if (p2 != -1)
			edge.push_back({i, p2});
	}
}

int construct_roads(std::vector<int> _X, std::vector<int> _Y) {
	X = _X; Y = _Y;
	n = X.size();
	if (n == 1) {
		build({}, {}, {}, {});
		return 1;
	}
	Loop (i,0,n)
		pts[pii(X[i], Y[i])] = i;
	make_edges();
	//for (auto [x, y] : edge)
	//	cerr << X[x] << ' ' << Y[x] << " - " << X[y] << ' ' << Y[y] << '\n';
	mt19937_64 rd(time(0));
	while (clock() < 3*CLOCKS_PER_SEC) {
		dsu::init(n);
		int cnt = 0;
		vector<pii> e;
		for (auto [x, y] : edge) {
			if (dsu::unite(x, y)) {
				e.emplace_back(x, y);
				++cnt;
			}
		}
		if (cnt != n-1)
			return 0;
		auto chairs = matching::get_match(e);
		//cerr << "found!\n";
		//for (auto [x, y] : chairs)
		//	cerr << x << ' ' << y << '\n';
		if (chairs.empty())
			continue;
		vector<int> ex, ey, cx, cy;
		Loop (i,0,n-1) {
			ex.push_back(e[i].first);
			ey.push_back(e[i].second);
			cx.push_back(chairs[i].first);
			cy.push_back(chairs[i].second);
		}
		build(ex, ey, cx, cy);
		return 1;
	}
	return 0;
}

Compilation message

parks.cpp: In function 'bool matching::bfs(int)':
parks.cpp:3:40: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    3 | #define Loop(x,l,r) for (ll x = (l); x < (r); ++x)
      |                                        ^
parks.cpp:55:3: note: in expansion of macro 'Loop'
   55 |   Loop (i,0,q.size()) {
      |   ^~~~
parks.cpp: In function 'std::vector<std::pair<int, int> > matching::get_match(std::vector<std::pair<int, int> >)':
parks.cpp:3:40: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    3 | #define Loop(x,l,r) for (ll x = (l); x < (r); ++x)
      |                                        ^
parks.cpp:97:3: note: in expansion of macro 'Loop'
   97 |   Loop (i,0,m+chairs.size()) {
      |   ^~~~

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 14292 KB Output is correct
2 Correct 7 ms 14292 KB Output is correct
3 Correct 8 ms 14292 KB Output is correct
4 Correct 7 ms 14292 KB Output is correct
5 Correct 6 ms 14292 KB Output is correct
6 Correct 6 ms 14292 KB Output is correct
7 Correct 6 ms 14292 KB Output is correct
8 Correct 6 ms 14292 KB Output is correct
9 Correct 171 ms 44800 KB Output is correct
10 Correct 21 ms 17556 KB Output is correct
11 Correct 69 ms 30700 KB Output is correct
12 Correct 22 ms 18952 KB Output is correct
13 Correct 29 ms 19396 KB Output is correct
14 Correct 7 ms 14420 KB Output is correct
15 Correct 7 ms 14548 KB Output is correct
16 Correct 190 ms 44800 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 14292 KB Output is correct
2 Correct 7 ms 14292 KB Output is correct
3 Correct 8 ms 14292 KB Output is correct
4 Correct 7 ms 14292 KB Output is correct
5 Correct 6 ms 14292 KB Output is correct
6 Correct 6 ms 14292 KB Output is correct
7 Correct 6 ms 14292 KB Output is correct
8 Correct 6 ms 14292 KB Output is correct
9 Correct 171 ms 44800 KB Output is correct
10 Correct 21 ms 17556 KB Output is correct
11 Correct 69 ms 30700 KB Output is correct
12 Correct 22 ms 18952 KB Output is correct
13 Correct 29 ms 19396 KB Output is correct
14 Correct 7 ms 14420 KB Output is correct
15 Correct 7 ms 14548 KB Output is correct
16 Correct 190 ms 44800 KB Output is correct
17 Correct 6 ms 14364 KB Output is correct
18 Correct 7 ms 14400 KB Output is correct
19 Correct 6 ms 14292 KB Output is correct
20 Correct 7 ms 14292 KB Output is correct
21 Correct 7 ms 14400 KB Output is correct
22 Correct 6 ms 14292 KB Output is correct
23 Correct 472 ms 71272 KB Output is correct
24 Correct 6 ms 14292 KB Output is correct
25 Correct 7 ms 14676 KB Output is correct
26 Correct 10 ms 14676 KB Output is correct
27 Correct 8 ms 14748 KB Output is correct
28 Correct 147 ms 36796 KB Output is correct
29 Correct 215 ms 48336 KB Output is correct
30 Correct 365 ms 59364 KB Output is correct
31 Correct 419 ms 71252 KB Output is correct
32 Correct 6 ms 14368 KB Output is correct
33 Correct 6 ms 14292 KB Output is correct
34 Correct 6 ms 14292 KB Output is correct
35 Correct 8 ms 14348 KB Output is correct
36 Correct 6 ms 14292 KB Output is correct
37 Correct 7 ms 14336 KB Output is correct
38 Correct 7 ms 14376 KB Output is correct
39 Correct 7 ms 14292 KB Output is correct
40 Correct 7 ms 14340 KB Output is correct
41 Correct 8 ms 14292 KB Output is correct
42 Correct 6 ms 14292 KB Output is correct
43 Correct 7 ms 14548 KB Output is correct
44 Correct 8 ms 14712 KB Output is correct
45 Correct 254 ms 42380 KB Output is correct
46 Correct 340 ms 56144 KB Output is correct
47 Correct 335 ms 56052 KB Output is correct

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 14292 KB Output is correct
2 Correct 7 ms 14292 KB Output is correct
3 Correct 8 ms 14292 KB Output is correct
4 Correct 7 ms 14292 KB Output is correct
5 Correct 6 ms 14292 KB Output is correct
6 Correct 6 ms 14292 KB Output is correct
7 Correct 6 ms 14292 KB Output is correct
8 Correct 6 ms 14292 KB Output is correct
9 Correct 171 ms 44800 KB Output is correct
10 Correct 21 ms 17556 KB Output is correct
11 Correct 69 ms 30700 KB Output is correct
12 Correct 22 ms 18952 KB Output is correct
13 Correct 29 ms 19396 KB Output is correct
14 Correct 7 ms 14420 KB Output is correct
15 Correct 7 ms 14548 KB Output is correct
16 Correct 190 ms 44800 KB Output is correct
17 Correct 6 ms 14364 KB Output is correct
18 Correct 7 ms 14400 KB Output is correct
19 Correct 6 ms 14292 KB Output is correct
20 Correct 7 ms 14292 KB Output is correct
21 Correct 7 ms 14400 KB Output is correct
22 Correct 6 ms 14292 KB Output is correct
23 Correct 472 ms 71272 KB Output is correct
24 Correct 6 ms 14292 KB Output is correct
25 Correct 7 ms 14676 KB Output is correct
26 Correct 10 ms 14676 KB Output is correct
27 Correct 8 ms 14748 KB Output is correct
28 Correct 147 ms 36796 KB Output is correct
29 Correct 215 ms 48336 KB Output is correct
30 Correct 365 ms 59364 KB Output is correct
31 Correct 419 ms 71252 KB Output is correct
32 Correct 6 ms 14368 KB Output is correct
33 Correct 6 ms 14292 KB Output is correct
34 Correct 6 ms 14292 KB Output is correct
35 Correct 8 ms 14348 KB Output is correct
36 Correct 6 ms 14292 KB Output is correct
37 Correct 7 ms 14336 KB Output is correct
38 Correct 7 ms 14376 KB Output is correct
39 Correct 7 ms 14292 KB Output is correct
40 Correct 7 ms 14340 KB Output is correct
41 Correct 8 ms 14292 KB Output is correct
42 Correct 6 ms 14292 KB Output is correct
43 Correct 7 ms 14548 KB Output is correct
44 Correct 8 ms 14712 KB Output is correct
45 Correct 254 ms 42380 KB Output is correct
46 Correct 340 ms 56144 KB Output is correct
47 Correct 335 ms 56052 KB Output is correct
48 Correct 6 ms 14292 KB Output is correct
49 Correct 6 ms 14292 KB Output is correct
50 Correct 6 ms 14292 KB Output is correct
51 Correct 6 ms 14292 KB Output is correct
52 Correct 6 ms 14292 KB Output is correct
53 Correct 7 ms 14396 KB Output is correct
54 Correct 7 ms 14292 KB Output is correct
55 Incorrect 3165 ms 59124 KB Solution announced impossible, but it is possible.
56 Halted 0 ms 0 KB -

Subtask #4
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 14292 KB Output is correct
2 Correct 7 ms 14292 KB Output is correct
3 Correct 8 ms 14292 KB Output is correct
4 Correct 7 ms 14292 KB Output is correct
5 Correct 6 ms 14292 KB Output is correct
6 Correct 6 ms 14292 KB Output is correct
7 Correct 6 ms 14292 KB Output is correct
8 Correct 6 ms 14292 KB Output is correct
9 Correct 171 ms 44800 KB Output is correct
10 Correct 21 ms 17556 KB Output is correct
11 Correct 69 ms 30700 KB Output is correct
12 Correct 22 ms 18952 KB Output is correct
13 Correct 29 ms 19396 KB Output is correct
14 Correct 7 ms 14420 KB Output is correct
15 Correct 7 ms 14548 KB Output is correct
16 Correct 190 ms 44800 KB Output is correct
17 Correct 7 ms 14292 KB Output is correct
18 Correct 8 ms 14292 KB Output is correct
19 Correct 7 ms 14292 KB Output is correct
20 Correct 526 ms 68496 KB Output is correct
21 Correct 482 ms 68348 KB Output is correct
22 Correct 518 ms 68320 KB Output is correct
23 Correct 349 ms 67104 KB Output is correct
24 Correct 173 ms 32356 KB Output is correct
25 Correct 338 ms 37024 KB Output is correct
26 Correct 246 ms 36928 KB Output is correct
27 Correct 502 ms 75520 KB Output is correct
28 Correct 527 ms 75392 KB Output is correct
29 Correct 580 ms 75384 KB Output is correct
30 Correct 599 ms 75344 KB Output is correct
31 Correct 6 ms 14292 KB Output is correct
32 Correct 32 ms 18440 KB Output is correct
33 Correct 89 ms 23396 KB Output is correct
34 Correct 448 ms 68512 KB Output is correct
35 Correct 13 ms 15572 KB Output is correct
36 Correct 47 ms 19928 KB Output is correct
37 Correct 107 ms 25688 KB Output is correct
38 Correct 155 ms 36972 KB Output is correct
39 Correct 242 ms 44672 KB Output is correct
40 Correct 354 ms 54412 KB Output is correct
41 Correct 427 ms 62204 KB Output is correct
42 Correct 620 ms 70048 KB Output is correct
43 Correct 6 ms 14292 KB Output is correct
44 Correct 7 ms 14292 KB Output is correct
45 Correct 6 ms 14292 KB Output is correct
46 Correct 6 ms 14296 KB Output is correct
47 Correct 6 ms 14292 KB Output is correct
48 Correct 8 ms 14292 KB Output is correct
49 Correct 7 ms 14292 KB Output is correct
50 Correct 7 ms 14404 KB Output is correct
51 Correct 8 ms 14292 KB Output is correct
52 Correct 8 ms 14368 KB Output is correct
53 Correct 8 ms 14292 KB Output is correct
54 Correct 9 ms 14616 KB Output is correct
55 Correct 11 ms 14676 KB Output is correct
56 Correct 185 ms 42388 KB Output is correct
57 Correct 335 ms 56100 KB Output is correct
58 Correct 309 ms 56124 KB Output is correct
59 Correct 8 ms 14300 KB Output is correct
60 Correct 7 ms 14292 KB Output is correct
61 Correct 7 ms 14292 KB Output is correct
62 Correct 459 ms 75512 KB Output is correct
63 Correct 407 ms 75392 KB Output is correct
64 Correct 513 ms 75236 KB Output is correct
65 Correct 10 ms 14804 KB Output is correct
66 Correct 11 ms 15188 KB Output is correct
67 Correct 186 ms 42108 KB Output is correct
68 Correct 341 ms 57148 KB Output is correct
69 Correct 564 ms 70220 KB Output is correct

Subtask #5
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 14292 KB Output is correct
2 Correct 7 ms 14292 KB Output is correct
3 Correct 8 ms 14292 KB Output is correct
4 Correct 7 ms 14292 KB Output is correct
5 Correct 6 ms 14292 KB Output is correct
6 Correct 6 ms 14292 KB Output is correct
7 Correct 6 ms 14292 KB Output is correct
8 Correct 6 ms 14292 KB Output is correct
9 Correct 171 ms 44800 KB Output is correct
10 Correct 21 ms 17556 KB Output is correct
11 Correct 69 ms 30700 KB Output is correct
12 Correct 22 ms 18952 KB Output is correct
13 Correct 29 ms 19396 KB Output is correct
14 Correct 7 ms 14420 KB Output is correct
15 Correct 7 ms 14548 KB Output is correct
16 Correct 190 ms 44800 KB Output is correct
17 Correct 467 ms 75900 KB Output is correct
18 Correct 537 ms 76060 KB Output is correct
19 Correct 616 ms 68312 KB Output is correct
20 Correct 605 ms 68772 KB Output is correct
21 Correct 500 ms 65976 KB Output is correct
22 Correct 7 ms 14292 KB Output is correct
23 Correct 66 ms 23468 KB Output is correct
24 Correct 22 ms 16788 KB Output is correct
25 Correct 83 ms 23000 KB Output is correct
26 Correct 176 ms 28220 KB Output is correct
27 Correct 210 ms 42464 KB Output is correct
28 Correct 257 ms 50360 KB Output is correct
29 Correct 313 ms 57544 KB Output is correct
30 Correct 456 ms 63852 KB Output is correct
31 Correct 533 ms 70704 KB Output is correct
32 Correct 548 ms 71508 KB Output is correct
33 Correct 471 ms 75516 KB Output is correct
34 Correct 10 ms 14932 KB Output is correct
35 Correct 16 ms 15384 KB Output is correct
36 Correct 226 ms 42292 KB Output is correct
37 Correct 307 ms 57376 KB Output is correct
38 Correct 502 ms 70464 KB Output is correct

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 14292 KB Output is correct
2 Correct 7 ms 14292 KB Output is correct
3 Correct 8 ms 14292 KB Output is correct
4 Correct 7 ms 14292 KB Output is correct
5 Correct 6 ms 14292 KB Output is correct
6 Correct 6 ms 14292 KB Output is correct
7 Correct 6 ms 14292 KB Output is correct
8 Correct 6 ms 14292 KB Output is correct
9 Correct 171 ms 44800 KB Output is correct
10 Correct 21 ms 17556 KB Output is correct
11 Correct 69 ms 30700 KB Output is correct
12 Correct 22 ms 18952 KB Output is correct
13 Correct 29 ms 19396 KB Output is correct
14 Correct 7 ms 14420 KB Output is correct
15 Correct 7 ms 14548 KB Output is correct
16 Correct 190 ms 44800 KB Output is correct
17 Correct 6 ms 14364 KB Output is correct
18 Correct 7 ms 14400 KB Output is correct
19 Correct 6 ms 14292 KB Output is correct
20 Correct 7 ms 14292 KB Output is correct
21 Correct 7 ms 14400 KB Output is correct
22 Correct 6 ms 14292 KB Output is correct
23 Correct 472 ms 71272 KB Output is correct
24 Correct 6 ms 14292 KB Output is correct
25 Correct 7 ms 14676 KB Output is correct
26 Correct 10 ms 14676 KB Output is correct
27 Correct 8 ms 14748 KB Output is correct
28 Correct 147 ms 36796 KB Output is correct
29 Correct 215 ms 48336 KB Output is correct
30 Correct 365 ms 59364 KB Output is correct
31 Correct 419 ms 71252 KB Output is correct
32 Correct 6 ms 14368 KB Output is correct
33 Correct 6 ms 14292 KB Output is correct
34 Correct 6 ms 14292 KB Output is correct
35 Correct 8 ms 14348 KB Output is correct
36 Correct 6 ms 14292 KB Output is correct
37 Correct 7 ms 14336 KB Output is correct
38 Correct 7 ms 14376 KB Output is correct
39 Correct 7 ms 14292 KB Output is correct
40 Correct 7 ms 14340 KB Output is correct
41 Correct 8 ms 14292 KB Output is correct
42 Correct 6 ms 14292 KB Output is correct
43 Correct 7 ms 14548 KB Output is correct
44 Correct 8 ms 14712 KB Output is correct
45 Correct 254 ms 42380 KB Output is correct
46 Correct 340 ms 56144 KB Output is correct
47 Correct 335 ms 56052 KB Output is correct
48 Correct 6 ms 14292 KB Output is correct
49 Correct 6 ms 14292 KB Output is correct
50 Correct 6 ms 14292 KB Output is correct
51 Correct 6 ms 14292 KB Output is correct
52 Correct 6 ms 14292 KB Output is correct
53 Correct 7 ms 14396 KB Output is correct
54 Correct 7 ms 14292 KB Output is correct
55 Incorrect 3165 ms 59124 KB Solution announced impossible, but it is possible.
56 Halted 0 ms 0 KB -