oj.uz

Submission #727286

# Submission time Handle Problem Language Result Execution time Memory
727286 2023-04-20T11:13:16 Z ono_de206 Beads and wires (APIO14_beads) C++14
100 / 100
 186 ms 25872 KB 
#include<bits/stdc++.h>
using namespace std;

#define fast ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define in insert
#define all(x) x.begin(),x.end()
#define pb push_back
#define eb emplace_back
#define ff first
#define ss second

#define int long long
 
typedef long long ll;
typedef vector<int> vi;
typedef set<int> si;
typedef multiset<int> msi;
typedef pair<int, int> pii;
typedef vector<pii> vpii;

template<typename T, typename U>
ostream & operator << (ostream &out, const pair<T, U> &c) {
	out << c.first << ' ' << c.second;
    return out;
}

template<typename T>
ostream & operator << (ostream &out, vector<T> &v) {
	const int sz = v.size();
	for (int i = 0; i < sz; i++) {
		if (i) out << ' ';
		out << v[i];
	}
    return out;
}

template<typename T>
istream & operator >> (istream &in, vector<T> &v) {
	for (T &x : v) in >> x;
    return in;
}


template<typename T>
void mxx(T &a, T b){if(b > a) a = b;}
template<typename T>
void mnn(T &a, T b){if(b < a) a = b;}

const int mxn = 2e5 + 10, inf = 1e18;
int n, f[mxn], g[mxn], ans;
vector<pair<int, int>> adj[mxn];

void dfs1(int to, int fr) {
	f[to] = 0;
	g[to] = -inf;
	int mx1 = -inf;
	for(auto it : adj[to]) {
		if(it.ff == fr) continue;
		int x = it.ff;
		dfs1(x, to);
		f[to] += max(f[x], g[x] + it.ss);
		mxx(mx1, f[x] + it.ss - max(f[x], g[x] + it.ss));
	}
	mxx(g[to], f[to] + mx1);
}

void dfs2(int to, int fr, int pf, int pg) {
	int sumf = pf + f[to];
	int mx1 = pg - pf, mx2 = -inf;
	mxx(ans, sumf);
	for(auto it : adj[to]) {
		if(it.ff == fr) continue;
		int x = it.ff;
		int tmp = f[x] + it.ss - max(g[x] + it.ss, f[x]);
		if(tmp > mx1) {
			mx2 = mx1;
			mx1 = tmp;
		} else if(tmp > mx2) {
			mx2 = tmp;
		}
	}
	for(auto it : adj[to]) {
		if(it.ff == fr) continue;
		int x = it.ff;
		sumf -= max(g[x] + it.ss, f[x]);
		int ll = (f[x] + it.ss - max(g[x] + it.ss, f[x]) == mx1 ? mx2 : mx1);
		// if(x == 3 && to == 1) {
		// 	cout << ll << ' ' << sumf << ' ' << it.ss << '\n';
		// }
		dfs2(x, to, max(sumf, it.ss + sumf + ll), sumf + it.ss);
		sumf += max(g[x] + it.ss, f[x]);
	}
}

void go() {
	cin >> n;
	for(int i = 1; i < n; i++) {
		int x, y, c;
		cin >> x >> y >> c;
		adj[x].eb(y, c);
		adj[y].eb(x, c);
	}
	dfs1(1, 0);
	dfs2(1, 0, 0, -inf);
	cout << ans << '\n';
}
 
signed main() {
	// #ifndef ONO
	// freopen("beads.in", "r", stdin);
	// freopen("beads.out", "w", stdout);
	// #endif
	fast;
	int t = 1;
	// cin >> t;
	while(t--) {
		go();
	}
	return 0;
}

Subtask #1
13.0 / 13.0

# 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 2 ms 4948 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 4948 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 3 ms 4948 KB Output is correct
8 Correct 3 ms 4948 KB Output is correct
9 Correct 3 ms 5028 KB Output is correct
10 Correct 3 ms 4948 KB Output is correct
11 Correct 3 ms 4948 KB Output is correct
12 Correct 3 ms 5028 KB Output is correct

Subtask #2
15.0 / 15.0

# 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 2 ms 4948 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 4948 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 3 ms 4948 KB Output is correct
8 Correct 3 ms 4948 KB Output is correct
9 Correct 3 ms 5028 KB Output is correct
10 Correct 3 ms 4948 KB Output is correct
11 Correct 3 ms 4948 KB Output is correct
12 Correct 3 ms 5028 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Correct 3 ms 5028 KB Output is correct
15 Correct 3 ms 5020 KB Output is correct
16 Correct 3 ms 4948 KB Output is correct
17 Correct 3 ms 4948 KB Output is correct
18 Correct 3 ms 4948 KB Output is correct
19 Correct 3 ms 5024 KB Output is correct
20 Correct 3 ms 4948 KB Output is correct
21 Correct 3 ms 4948 KB Output is correct
22 Correct 3 ms 5032 KB Output is correct

Subtask #3
29.0 / 29.0

# 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 2 ms 4948 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 4948 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 3 ms 4948 KB Output is correct
8 Correct 3 ms 4948 KB Output is correct
9 Correct 3 ms 5028 KB Output is correct
10 Correct 3 ms 4948 KB Output is correct
11 Correct 3 ms 4948 KB Output is correct
12 Correct 3 ms 5028 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Correct 3 ms 5028 KB Output is correct
15 Correct 3 ms 5020 KB Output is correct
16 Correct 3 ms 4948 KB Output is correct
17 Correct 3 ms 4948 KB Output is correct
18 Correct 3 ms 4948 KB Output is correct
19 Correct 3 ms 5024 KB Output is correct
20 Correct 3 ms 4948 KB Output is correct
21 Correct 3 ms 4948 KB Output is correct
22 Correct 3 ms 5032 KB Output is correct
23 Correct 5 ms 5420 KB Output is correct
24 Correct 5 ms 5332 KB Output is correct
25 Correct 5 ms 5332 KB Output is correct
26 Correct 7 ms 5844 KB Output is correct
27 Correct 7 ms 5808 KB Output is correct
28 Correct 8 ms 5804 KB Output is correct
29 Correct 7 ms 5748 KB Output is correct
30 Correct 6 ms 5716 KB Output is correct
31 Correct 7 ms 6100 KB Output is correct

Subtask #4
43.0 / 43.0

# 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 2 ms 4948 KB Output is correct
4 Correct 3 ms 4948 KB Output is correct
5 Correct 3 ms 4948 KB Output is correct
6 Correct 3 ms 4948 KB Output is correct
7 Correct 3 ms 4948 KB Output is correct
8 Correct 3 ms 4948 KB Output is correct
9 Correct 3 ms 5028 KB Output is correct
10 Correct 3 ms 4948 KB Output is correct
11 Correct 3 ms 4948 KB Output is correct
12 Correct 3 ms 5028 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Correct 3 ms 5028 KB Output is correct
15 Correct 3 ms 5020 KB Output is correct
16 Correct 3 ms 4948 KB Output is correct
17 Correct 3 ms 4948 KB Output is correct
18 Correct 3 ms 4948 KB Output is correct
19 Correct 3 ms 5024 KB Output is correct
20 Correct 3 ms 4948 KB Output is correct
21 Correct 3 ms 4948 KB Output is correct
22 Correct 3 ms 5032 KB Output is correct
23 Correct 5 ms 5420 KB Output is correct
24 Correct 5 ms 5332 KB Output is correct
25 Correct 5 ms 5332 KB Output is correct
26 Correct 7 ms 5844 KB Output is correct
27 Correct 7 ms 5808 KB Output is correct
28 Correct 8 ms 5804 KB Output is correct
29 Correct 7 ms 5748 KB Output is correct
30 Correct 6 ms 5716 KB Output is correct
31 Correct 7 ms 6100 KB Output is correct
32 Correct 28 ms 9132 KB Output is correct
33 Correct 29 ms 8996 KB Output is correct
34 Correct 28 ms 9016 KB Output is correct
35 Correct 186 ms 21896 KB Output is correct
36 Correct 173 ms 21932 KB Output is correct
37 Correct 178 ms 21804 KB Output is correct
38 Correct 111 ms 21156 KB Output is correct
39 Correct 112 ms 21016 KB Output is correct
40 Correct 113 ms 21064 KB Output is correct
41 Correct 180 ms 25872 KB Output is correct