oj.uz

Submission #551722

# Submission time Handle Problem Language Result Execution time Memory
551722 2022-04-21T11:35:23 Z GioChkhaidze Meetings 2 (JOI21_meetings2) C++14
100 / 100
 594 ms 74756 KB 
#include <bits/stdc++.h>

#define pb push_back
#define f first
#define s second

using namespace std;

const int N = 2e5 + 5;

int n;
int timer, in[N], out[N], dep[N], tot[N], ans[N], P[N][20];
vector < int > v[N];
set < int > st[N];

bool is_anc(int a, int b) {
	return (in[a] <= in[b] && out[b] <= out[a]);
}

int LCA(int a, int b) {
	if (dep[a] > dep[b]) swap(a, b);
	if (is_anc(a, b)) return a;
	for (int j = 18; j >= 0; --j) 
		if (!is_anc(P[a][j], b)) a = P[a][j];
	return P[a][0];
}

int dst(int a, int b) {
	return dep[a] + dep[b] - 2 * dep[LCA(a, b)] + 1;
}

void dfs(int x, int p) {
	dep[x] = dep[p] + 1;
	in[x] = ++timer;
	P[x][0] = p;
	for (int j = 1; j <= 18; ++j) {
		P[x][j] = P[P[x][j - 1]][j - 1];
	}
	for (int i = 0; i < v[x].size(); ++i) {
		int to = v[x][i];
		if (to == p) continue;
		dfs(to, x);
	}
	out[x] = timer;
}

main () {
	ios::sync_with_stdio(false);
	cin.tie(NULL), cout.tie(NULL);
	cin >> n;
	for (int i = 1; i < n; ++i) {
		int a, b;
		cin >> a >> b;
		v[a].pb(b);
		v[b].pb(a);
		st[a].insert(b);
		st[b].insert(a);
	}
	
	dfs(1, 1);
	set < pair < int , int > > S;
	for (int i = 1; i <= n; ++i) {
		tot[i] = 1;
		if (v[i].size() == 1) {
			S.insert({tot[i], i});
		}
	}
	
	vector < pair < int , int > > rec;
	while (S.size()) {
		int x = (*S.begin()).s;
		S.erase(S.find(*S.begin()));
		if (st[x].size() == 1) {
			int y = (*st[x].begin());
			rec.pb({x, tot[x]});
			tot[y] += tot[x];
			st[y].erase(st[y].find(x));
			st[x].erase(st[x].find(y));
			if (st[y].size() == 1) {
				S.insert({tot[y], y});
			}
		}
	}
	
	int str = 1;
	for (int i = 1; i <= n; ++i) {
		if (tot[i] == n) str = i;
	}
	
	int a0 = str, b0 = str, dm = 1;
	for (int i = n; i >= 1; --i) {
		if (i % 2 == 1) {
			ans[i] = 1;
		}
			else {
			while (rec.size() && rec.back().s >= i / 2) {
				int x = rec.back().f, a1 = dst(a0, x), b1 = dst(b0, x);
				rec.pop_back();
				if (a1 <= b1) {
					if (dm < b1) dm = b1, a0 = x;
				}
					else 
				if (b1 < a1) {
					if (dm < a1) dm = a1, b0 = x;
				}
			}
			ans[i] = dm;		
		}
	}
	
	for (int i = 1; i <= n; ++i) {
		cout << ans[i] << "\n";
	} 
}

Compilation message

meetings2.cpp: In function 'void dfs(int, int)':
meetings2.cpp:39:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   39 |  for (int i = 0; i < v[x].size(); ++i) {
      |                  ~~^~~~~~~~~~~~~
meetings2.cpp: At global scope:
meetings2.cpp:47:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   47 | main () {
      | ^~~~

Subtask #1
4.0 / 4.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 14420 KB Output is correct
2 Correct 10 ms 14396 KB Output is correct
3 Correct 10 ms 14384 KB Output is correct
4 Correct 10 ms 14420 KB Output is correct
5 Correct 11 ms 14420 KB Output is correct
6 Correct 8 ms 14420 KB Output is correct
7 Correct 8 ms 14420 KB Output is correct
8 Correct 8 ms 14420 KB Output is correct
9 Correct 8 ms 14420 KB Output is correct
10 Correct 8 ms 14324 KB Output is correct
11 Correct 7 ms 14344 KB Output is correct
12 Correct 8 ms 14420 KB Output is correct
13 Correct 7 ms 14420 KB Output is correct
14 Correct 8 ms 14428 KB Output is correct
15 Correct 8 ms 14420 KB Output is correct
16 Correct 9 ms 14360 KB Output is correct
17 Correct 8 ms 14420 KB Output is correct
18 Correct 8 ms 14420 KB Output is correct
19 Correct 8 ms 14408 KB Output is correct
20 Correct 7 ms 14420 KB Output is correct
21 Correct 8 ms 14416 KB Output is correct

Subtask #2
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 14420 KB Output is correct
2 Correct 10 ms 14396 KB Output is correct
3 Correct 10 ms 14384 KB Output is correct
4 Correct 10 ms 14420 KB Output is correct
5 Correct 11 ms 14420 KB Output is correct
6 Correct 8 ms 14420 KB Output is correct
7 Correct 8 ms 14420 KB Output is correct
8 Correct 8 ms 14420 KB Output is correct
9 Correct 8 ms 14420 KB Output is correct
10 Correct 8 ms 14324 KB Output is correct
11 Correct 7 ms 14344 KB Output is correct
12 Correct 8 ms 14420 KB Output is correct
13 Correct 7 ms 14420 KB Output is correct
14 Correct 8 ms 14428 KB Output is correct
15 Correct 8 ms 14420 KB Output is correct
16 Correct 9 ms 14360 KB Output is correct
17 Correct 8 ms 14420 KB Output is correct
18 Correct 8 ms 14420 KB Output is correct
19 Correct 8 ms 14408 KB Output is correct
20 Correct 7 ms 14420 KB Output is correct
21 Correct 8 ms 14416 KB Output is correct
22 Correct 14 ms 15508 KB Output is correct
23 Correct 13 ms 15464 KB Output is correct
24 Correct 13 ms 15444 KB Output is correct
25 Correct 14 ms 15456 KB Output is correct
26 Correct 13 ms 15444 KB Output is correct
27 Correct 13 ms 15456 KB Output is correct
28 Correct 16 ms 15536 KB Output is correct
29 Correct 14 ms 15444 KB Output is correct
30 Correct 13 ms 15468 KB Output is correct
31 Correct 12 ms 15464 KB Output is correct
32 Correct 12 ms 15572 KB Output is correct
33 Correct 12 ms 15540 KB Output is correct
34 Correct 13 ms 15456 KB Output is correct
35 Correct 13 ms 15584 KB Output is correct
36 Correct 13 ms 15444 KB Output is correct
37 Correct 14 ms 15576 KB Output is correct
38 Correct 16 ms 15560 KB Output is correct

Subtask #3
80.0 / 80.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 14420 KB Output is correct
2 Correct 10 ms 14396 KB Output is correct
3 Correct 10 ms 14384 KB Output is correct
4 Correct 10 ms 14420 KB Output is correct
5 Correct 11 ms 14420 KB Output is correct
6 Correct 8 ms 14420 KB Output is correct
7 Correct 8 ms 14420 KB Output is correct
8 Correct 8 ms 14420 KB Output is correct
9 Correct 8 ms 14420 KB Output is correct
10 Correct 8 ms 14324 KB Output is correct
11 Correct 7 ms 14344 KB Output is correct
12 Correct 8 ms 14420 KB Output is correct
13 Correct 7 ms 14420 KB Output is correct
14 Correct 8 ms 14428 KB Output is correct
15 Correct 8 ms 14420 KB Output is correct
16 Correct 9 ms 14360 KB Output is correct
17 Correct 8 ms 14420 KB Output is correct
18 Correct 8 ms 14420 KB Output is correct
19 Correct 8 ms 14408 KB Output is correct
20 Correct 7 ms 14420 KB Output is correct
21 Correct 8 ms 14416 KB Output is correct
22 Correct 14 ms 15508 KB Output is correct
23 Correct 13 ms 15464 KB Output is correct
24 Correct 13 ms 15444 KB Output is correct
25 Correct 14 ms 15456 KB Output is correct
26 Correct 13 ms 15444 KB Output is correct
27 Correct 13 ms 15456 KB Output is correct
28 Correct 16 ms 15536 KB Output is correct
29 Correct 14 ms 15444 KB Output is correct
30 Correct 13 ms 15468 KB Output is correct
31 Correct 12 ms 15464 KB Output is correct
32 Correct 12 ms 15572 KB Output is correct
33 Correct 12 ms 15540 KB Output is correct
34 Correct 13 ms 15456 KB Output is correct
35 Correct 13 ms 15584 KB Output is correct
36 Correct 13 ms 15444 KB Output is correct
37 Correct 14 ms 15576 KB Output is correct
38 Correct 16 ms 15560 KB Output is correct
39 Correct 594 ms 67468 KB Output is correct
40 Correct 571 ms 66432 KB Output is correct
41 Correct 587 ms 67644 KB Output is correct
42 Correct 592 ms 68552 KB Output is correct
43 Correct 559 ms 68580 KB Output is correct
44 Correct 553 ms 68552 KB Output is correct
45 Correct 530 ms 71332 KB Output is correct
46 Correct 355 ms 71144 KB Output is correct
47 Correct 504 ms 70828 KB Output is correct
48 Correct 493 ms 74044 KB Output is correct
49 Correct 460 ms 69024 KB Output is correct
50 Correct 438 ms 73868 KB Output is correct
51 Correct 394 ms 74756 KB Output is correct