oj.uz

Submission #674437

# Submission time Handle Problem Language Result Execution time Memory
674437 2022-12-24T08:09:24 Z ghostwriter Beads and wires (APIO14_beads) C++17
100 / 100
 176 ms 21472 KB 
// #pragma GCC optimize ("Ofast")
// #pragma GCC target ("avx2")
#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
    #include <debug.h>
#else
    #define debug(...)
#endif
#define ft front
#define bk back
#define st first
#define nd second
#define ins insert
#define ers erase
#define pb push_back
#define pf push_front
#define _pb pop_back
#define _pf pop_front
#define lb lower_bound
#define ub upper_bound
#define mtp make_tuple
#define bg begin
#define ed end
#define all(x) (x).bg(), (x).ed()
#define sz(x) (int)(x).size()
// #define int long long
typedef long long ll; typedef unsigned long long ull;
typedef double db; typedef long double ldb;
typedef pair<int, int> pi; typedef pair<ll, ll> pll;
typedef vector<int> vi; typedef vector<ll> vll; typedef vector<pi> vpi; typedef vector<pll> vpll;
typedef string str;
#define FOR(i, l, r) for (int i = (l); i <= (r); ++i)
#define FOS(i, r, l) for (int i = (r); i >= (l); --i)
#define FRN(i, n) for (int i = 0; i < (n); ++i)
#define FSN(i, n) for (int i = (n) - 1; i >= 0; --i)
#define EACH(i, x) for (auto &i : (x))
#define WHILE while
template<typename T> T gcd(T a, T b) { T d2 = (a | b) & -(a | b); a /= d2; b /= d2; WHILE(b) { a = a % b; swap(a, b); } return a * d2; }
template<typename T> T lcm(T a, T b) { return a / gcd(a, b) * b; }
void _assert(bool statement) { if (statement) return; cerr << "\n>> Assertion failed!\n"; exit(0); }
void _assert(bool statement, const str &message) { if (statement) return; cerr << "\n>> Assertion failed: " << message << '\n'; exit(0); }
void _error(const str &message) { cerr << "\n>> Error: " << message << '\n'; exit(0); }
#define file "TEST"
mt19937 rd(chrono::steady_clock::now().time_since_epoch().count());
ll rand(ll l, ll r) { return uniform_int_distribution<ll>(l, r)(rd); }
/*
----------------------------------------------------------------
    END OF TEMPLATE
----------------------------------------------------------------
    Tran The Bao - ghostwriter
    Training for VOI23 gold medal
----------------------------------------------------------------
    GOAT
----------------------------------------------------------------
*/
const int oo = 1e9 + 5;
const int N = 2e5 + 5;
int n, d[N][2], rs = 0;
vpi adj[N];
void input(int test_id) {
	cin >> n;
	FOR(i, 1, n - 1) {
		int a, b, c;
		cin >> a >> b >> c;
		adj[a].pb({b, c});
		adj[b].pb({a, c});
	}
}
void dfs(int u, int p) {
	int sum = 0;
	EACH(j, adj[u]) {
		int v = j.st, w = j.nd;
		if (v == p) continue;
		dfs(v, u);
		d[u][0] += max(d[v][0], d[v][1] + w);
		sum += max(d[v][0], d[v][1] + w);
	}
	d[u][1] = -oo;
	EACH(j, adj[u]) {
		int v = j.st, w = j.nd;
		if (v == p) continue;
		d[u][1] = max(d[u][1], sum - max(d[v][0], d[v][1] + w) + d[v][0] + w);
	}
	// debug(u, 0, d[u][0]);
	// debug(u, 1, d[u][1]);
}
void dfs1(int u, int p, int pw, int d0, int d1) {
	int max1 = -oo, max2 = -oo;
	auto updm = [&](int v) {
		if (max1 < v) {
			max2 = max1;
			max1 = v;
		}
		else max2 = max(max2, v);
	};
	if (p) updm(d0 + pw - max(d0, d1 + pw));
	rs = max(rs, d[u][0] + max(d0, d1 + pw));
	int sum = 0;
	EACH(j, adj[u]) {
		int v = j.st, w = j.nd;
		if (v == p) continue;
		sum += max(d[v][0], d[v][1] + w);
		updm(d[v][0] + w - max(d[v][0], d[v][1] + w));
	}
	EACH(j, adj[u]) {
		int v = j.st, w = j.nd;
		if (v == p) continue;
		int s0 = sum - max(d[v][0], d[v][1] + w) + max(d0, d1 + pw), s1 = s0;
		if (max1 == d[v][0] + w - max(d[v][0], d[v][1] + w)) s1 += max2;
		else s1 += max1;
		dfs1(v, u, w, s0, s1);
	}
}
void solve(int test_id) {
	dfs(1, 0);
	dfs1(1, 0, 0, 0, 0);
	cout << rs;
}
void reinit(int test_id) {

}
signed main() {
    ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    // freopen(file".inp", "r", stdin);
    // freopen(file".out", "w", stdout);
    int test_num = 1;
    // cin >> test_num; // comment if the problem does not requires multitest
    FOR(i, 1, test_num) {
        input(i); // input in noninteractive problems for case #i
        solve(i); // main function to solve case #i
        reinit(i); // reinit global data to default used in case #i
    }
    #ifdef LOCAL
        cerr << "\nTime: " << setprecision(5) << fixed << (ldb)clock() / CLOCKS_PER_SEC << "ms.\n";
    #endif
    return 0;
}
/*
10
4 10 2
1 2 21
1 3 13
6 7 1
7 9 5
2 4 3
2 5 8
1 6 55
6 8 34
----------------------------------------------------------------
From Benq:
    stuff you should look for
        * int overflow, array bounds
        * special cases (n=1?)
        * do smth instead of nothing and stay organized
        * WRITE STUFF DOWN
        * DON'T GET STUCK ON ONE APPROACH
----------------------------------------------------------------
*/

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 3 ms 4948 KB Output is correct
4 Correct 2 ms 5028 KB Output is correct
5 Correct 2 ms 5032 KB Output is correct
6 Correct 3 ms 5036 KB Output is correct
7 Correct 2 ms 5028 KB Output is correct
8 Correct 2 ms 4948 KB Output is correct
9 Correct 3 ms 4948 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 4948 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 3 ms 4948 KB Output is correct
4 Correct 2 ms 5028 KB Output is correct
5 Correct 2 ms 5032 KB Output is correct
6 Correct 3 ms 5036 KB Output is correct
7 Correct 2 ms 5028 KB Output is correct
8 Correct 2 ms 4948 KB Output is correct
9 Correct 3 ms 4948 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 4948 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Correct 3 ms 5032 KB Output is correct
15 Correct 3 ms 5028 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 5036 KB Output is correct
19 Correct 2 ms 5028 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 5036 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 3 ms 4948 KB Output is correct
4 Correct 2 ms 5028 KB Output is correct
5 Correct 2 ms 5032 KB Output is correct
6 Correct 3 ms 5036 KB Output is correct
7 Correct 2 ms 5028 KB Output is correct
8 Correct 2 ms 4948 KB Output is correct
9 Correct 3 ms 4948 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 4948 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Correct 3 ms 5032 KB Output is correct
15 Correct 3 ms 5028 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 5036 KB Output is correct
19 Correct 2 ms 5028 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 5036 KB Output is correct
23 Correct 4 ms 5204 KB Output is correct
24 Correct 4 ms 5332 KB Output is correct
25 Correct 5 ms 5332 KB Output is correct
26 Correct 7 ms 5588 KB Output is correct
27 Correct 7 ms 5588 KB Output is correct
28 Correct 6 ms 5588 KB Output is correct
29 Correct 7 ms 5548 KB Output is correct
30 Correct 6 ms 5552 KB Output is correct
31 Correct 6 ms 5984 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 3 ms 4948 KB Output is correct
4 Correct 2 ms 5028 KB Output is correct
5 Correct 2 ms 5032 KB Output is correct
6 Correct 3 ms 5036 KB Output is correct
7 Correct 2 ms 5028 KB Output is correct
8 Correct 2 ms 4948 KB Output is correct
9 Correct 3 ms 4948 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 4948 KB Output is correct
13 Correct 3 ms 4948 KB Output is correct
14 Correct 3 ms 5032 KB Output is correct
15 Correct 3 ms 5028 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 5036 KB Output is correct
19 Correct 2 ms 5028 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 5036 KB Output is correct
23 Correct 4 ms 5204 KB Output is correct
24 Correct 4 ms 5332 KB Output is correct
25 Correct 5 ms 5332 KB Output is correct
26 Correct 7 ms 5588 KB Output is correct
27 Correct 7 ms 5588 KB Output is correct
28 Correct 6 ms 5588 KB Output is correct
29 Correct 7 ms 5548 KB Output is correct
30 Correct 6 ms 5552 KB Output is correct
31 Correct 6 ms 5984 KB Output is correct
32 Correct 25 ms 8012 KB Output is correct
33 Correct 25 ms 7940 KB Output is correct
34 Correct 37 ms 7936 KB Output is correct
35 Correct 158 ms 17496 KB Output is correct
36 Correct 147 ms 17484 KB Output is correct
37 Correct 156 ms 17560 KB Output is correct
38 Correct 94 ms 17848 KB Output is correct
39 Correct 89 ms 17840 KB Output is correct
40 Correct 96 ms 17784 KB Output is correct
41 Correct 176 ms 21472 KB Output is correct