oj.uz

답안 #310643

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
310643 2020-10-07T14:20:13 Z shivensinha4 Mag (COCI16_mag) C++17
120 / 120
 761 ms 250872 KB 
#include <bits/stdc++.h> 
using namespace std; 
#define for_(i, s, e) for (int i = s; i < (int) e; i++)
#define for__(i, s, e) for (ll i = s; i < e; i++)
typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> ii;
#define endl '\n'
 
const int MXN = 1e6;
const ll INF = 1e17;
vi adj[MXN+1];
int chain[MXN+1], val[MXN+1], n;
pair<ll, ll> ans = {INF, 1};
 
void update(ll nu, ll de) {
	ll g = __gcd(nu, de);
	pair<ll, ll> temp = {nu/g, de/g};
	if (ans.first == INF) ans = temp;
	else if (temp.first*ans.second < ans.first*temp.second) ans = temp;
}
 
 
void dfs(int p, int parent) {
	for (int i: adj[p]) if (i != parent) {
		dfs(i, p);
		chain[p] = max(chain[p], chain[i]);
	}
	
	if (val[p] == 1) chain[p] += 1;
	else chain[p] = 0;
}
 
 
void dfs2(int p, int parent, int pval) {
	vi all, mx(2);
	all.push_back(pval);
	for (int i: adj[p]) if (i != parent) all.push_back(chain[i]);
	sort(all.begin(), all.end(), greater<int>());
	for_(i, 0, min((int) all.size(), 2)) mx[i] = all[i];
	
	update(val[p], mx[0]+mx[1]+1);
	
	for (auto i: adj[p]) if (i != parent) dfs2(i, p, val[p] == 1 ? max(pval, mx[0] == chain[i] ? mx[1] : mx[0])+1 : 0);
}
 
 
int main() {
	#ifdef shiven
	freopen("test.in", "r", stdin);
	#endif
	
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	
	cin >> n;
	for_(i, 0, n-1) {
		int a, b; cin >> a >> b;
		a -= 1; b -= 1;
		adj[a].push_back(b); adj[b].push_back(a);
	}
	for_(i, 0, n) cin >> val[i];
	
	dfs(0, 0);
	dfs2(0, 0, 0);
	assert(ans.first != INF);
	cout << ans.first << "/" << ans.second << endl;
 
	return 0;
}

Subtask #1
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 19 ms 23936 KB Output is correct
2 Correct 17 ms 23936 KB Output is correct

Subtask #2
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 17 ms 23936 KB Output is correct
2 Correct 16 ms 23936 KB Output is correct

Subtask #3
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 578 ms 130300 KB Output is correct

Subtask #4
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 17 ms 23808 KB Output is correct
2 Correct 741 ms 248936 KB Output is correct

Subtask #5
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 718 ms 245244 KB Output is correct

Subtask #6
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 596 ms 62780 KB Output is correct
2 Correct 442 ms 53048 KB Output is correct

Subtask #7
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 543 ms 66916 KB Output is correct
2 Correct 110 ms 27876 KB Output is correct
3 Correct 761 ms 250872 KB Output is correct

Subtask #8
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 117 ms 27872 KB Output is correct
2 Correct 598 ms 64556 KB Output is correct
3 Correct 489 ms 43896 KB Output is correct

Subtask #9
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 542 ms 62960 KB Output is correct
2 Correct 567 ms 62328 KB Output is correct

Subtask #10
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 573 ms 63992 KB Output is correct
2 Correct 489 ms 43896 KB Output is correct