oj.uz

Submission #310644

# Submission time Handle Problem Language Result Execution time Memory
310644 2020-10-07T14:22:40 Z shivensinha4 Mag (COCI16_mag) C++17
120 / 120
 634 ms 219512 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);
	mx[0] = pval;
	for (int i: adj[p]) if (i != parent) {
		if (chain[i] >= mx[0]) mx = {chain[i], mx[0]};
		else mx[1] = max(mx[1], chain[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

# Verdict Execution time Memory Grader output
1 Correct 17 ms 23936 KB Output is correct
2 Correct 16 ms 23808 KB Output is correct

Subtask #2
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 23936 KB Output is correct
2 Correct 17 ms 23936 KB Output is correct

Subtask #3
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 491 ms 117708 KB Output is correct

Subtask #4
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 23808 KB Output is correct
2 Correct 632 ms 218076 KB Output is correct

Subtask #5
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 619 ms 214648 KB Output is correct

Subtask #6
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 478 ms 62860 KB Output is correct
2 Correct 355 ms 52856 KB Output is correct

Subtask #7
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 445 ms 63844 KB Output is correct
2 Correct 97 ms 27896 KB Output is correct
3 Correct 634 ms 219512 KB Output is correct

Subtask #8
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 110 ms 27916 KB Output is correct
2 Correct 474 ms 64120 KB Output is correct
3 Correct 428 ms 43900 KB Output is correct

Subtask #9
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 429 ms 62064 KB Output is correct
2 Correct 454 ms 62200 KB Output is correct

Subtask #10
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 474 ms 64000 KB Output is correct
2 Correct 453 ms 44024 KB Output is correct