Submission #879510

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
879510	2023-11-27T15:10:26 Z	marvinthang	Beads and wires (APIO14_beads)	C++17	100 / 100	101 ms	20180 KB

beads

/*************************************
*    author: marvinthang             *
*    created: 27.11.2023 20:59:10    *
*************************************/

#include <bits/stdc++.h>

using namespace std;

#define                  fi  first
#define                  se  second
#define                left  ___left
#define               right  ___right
#define                TIME  (1.0 * clock() / CLOCKS_PER_SEC)
#define             MASK(i)  (1LL << (i))
#define           BIT(x, i)  ((x) >> (i) & 1)
#define  __builtin_popcount  __builtin_popcountll
#define              ALL(v)  (v).begin(), (v).end()
#define           REP(i, n)  for (int i = 0, _n = (n); i < _n; ++i)
#define          REPD(i, n)  for (int i = (n); i-- > 0; )
#define        FOR(i, a, b)  for (int i = (a), _b = (b); i < _b; ++i) 
#define       FORD(i, b, a)  for (int i = (b), _a = (a); --i >= _a; ) 
#define       FORE(i, a, b)  for (int i = (a), _b = (b); i <= _b; ++i) 
#define      FORDE(i, b, a)  for (int i = (b), _a = (a); i >= _a; --i) 
#define        scan_op(...)  istream & operator >> (istream &in, __VA_ARGS__ &u)
#define       print_op(...)  ostream & operator << (ostream &out, const __VA_ARGS__ &u)
#ifdef LOCAL
    #include "debug.h"
#else
    #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
    #define DB(...) 23
    #define db(...) 23
    #define debug(...) 23
#endif

template <class U, class V> scan_op(pair <U, V>)  { return in >> u.first >> u.second; }
template <class T> scan_op(vector <T>)  { for (size_t i = 0; i < u.size(); ++i) in >> u[i]; return in; }
template <class U, class V> print_op(pair <U, V>)  { return out << '(' << u.first << ", " << u.second << ')'; }
template <size_t i, class T> ostream & print_tuple_utils(ostream &out, const T &tup) { if constexpr(i == tuple_size<T>::value) return out << ")";  else return print_tuple_utils<i + 1, T>(out << (i ? ", " : "(") << get<i>(tup), tup); }
template <class ...U> print_op(tuple<U...>) { return print_tuple_utils<0, tuple<U...>>(out, u); }
template <class Con, class = decltype(begin(declval<Con>()))> typename enable_if <!is_same<Con, string>::value, ostream&>::type operator << (ostream &out, const Con &con) { out << '{'; for (__typeof(con.begin()) it = con.begin(); it != con.end(); ++it) out << (it == con.begin() ? "" : ", ") << *it; return out << '}'; }
template <class A, class B> bool minimize(A &a, B b)  { if (a > b) { a = b; return true; } return false; }
template <class A, class B> bool maximize(A &a, B b)  { if (a < b) { a = b; return true; } return false; }

// end of template

const int INF = 1e9 + 7;

void process(void) {
	int n; cin >> n;
	vector <vector <pair <int, int>>> adj(n);	
	REP(i, n - 1) {
		int u, v, w; cin >> u >> v >> w;
		--u; --v;
		adj[u].emplace_back(w, v);
		adj[v].emplace_back(w, u);
	}
	vector <array <array <int, 2>, 2>> dp(n);
	function<void(int)> dfs = [&] (int u) {
		REP(a, 2) REP(b, 2) if (a || b) dp[u][a][b] = -INF;
		for (auto [w, v]: adj[u]) {
			adj[v].erase(find(ALL(adj[v]), pair {w, u}));
			dfs(v);
			REP(b, 2) dp[v][1][b] += w;
			dp[u][0][0] += max(dp[v][0][0], dp[v][1][0]);
		}
		pair <int, int> best_child(-INF, -INF);
		for (auto [w, v]: adj[u]) {
			int cur = max(dp[v][0][0], dp[v][0][1]) - max(dp[v][0][0], dp[v][1][0]) + w;
			if (best_child.fi < cur) best_child.se = best_child.fi, best_child.fi = cur;
			else maximize(best_child.se, cur);
		}
		for (auto [w, v]: adj[u]) {
			maximize(dp[u][0][1], dp[v][0][0] - max(dp[v][0][0], dp[v][1][0]) + w + (max(dp[v][0][0], dp[v][0][1]) - max(dp[v][0][0], dp[v][1][0]) + w == best_child.fi ? best_child.se : best_child.fi) + dp[u][0][0]);
		}
		for (auto [w, v]: adj[u]) {
			maximize(dp[u][0][1], max(dp[v][0][1], dp[v][1][1]) + dp[u][0][0] - max(dp[v][0][0], dp[v][1][0]));
			REP(b, 2) maximize(dp[u][1][b], dp[v][0][b] + w + dp[u][0][0] - max(dp[v][0][0], dp[v][1][0]));
		}
	};
	dfs(0);
	cout << max(dp[0][0][0], dp[0][0][1]) << '\n';
}

int main(void) {
	ios_base::sync_with_stdio(false); cin.tie(nullptr); // cout.tie(nullptr);
	file("beads");
	// int t; cin >> t; while (t--)
	process();
	// cerr << "Time elapsed: " << TIME << " s.\n";
	return (0^0);
}

Compilation message

beads.cpp: In function 'int main()':
beads.cpp:30:61: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |     #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
      |                                                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
beads.cpp:87:2: note: in expansion of macro 'file'
   87 |  file("beads");
      |  ^~~~
beads.cpp:30:94: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |     #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
      |                                                                                       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
beads.cpp:87:2: note: in expansion of macro 'file'
   87 |  file("beads");
      |  ^~~~

Subtask #1
13.0 / 13.0

#	Verdict	Memory	Grader output
1	Correct	344 KB	Output is correct
2	Correct	348 KB	Output is correct
3	Correct	424 KB	Output is correct
4	Correct	348 KB	Output is correct
5	Correct	348 KB	Output is correct
6	Correct	348 KB	Output is correct
7	Correct	348 KB	Output is correct
8	Correct	348 KB	Output is correct
9	Correct	348 KB	Output is correct
10	Correct	348 KB	Output is correct
11	Correct	348 KB	Output is correct
12	Correct	348 KB	Output is correct

Subtask #2
15.0 / 15.0

#	Verdict	Memory	Grader output
1	Correct	344 KB	Output is correct
2	Correct	348 KB	Output is correct
3	Correct	424 KB	Output is correct
4	Correct	348 KB	Output is correct
5	Correct	348 KB	Output is correct
6	Correct	348 KB	Output is correct
7	Correct	348 KB	Output is correct
8	Correct	348 KB	Output is correct
9	Correct	348 KB	Output is correct
10	Correct	348 KB	Output is correct
11	Correct	348 KB	Output is correct
12	Correct	348 KB	Output is correct
13	Correct	348 KB	Output is correct
14	Correct	348 KB	Output is correct
15	Correct	348 KB	Output is correct
16	Correct	348 KB	Output is correct
17	Correct	600 KB	Output is correct
18	Correct	348 KB	Output is correct
19	Correct	348 KB	Output is correct
20	Correct	348 KB	Output is correct
21	Correct	348 KB	Output is correct
22	Correct	348 KB	Output is correct

Subtask #3
29.0 / 29.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	344 KB	Output is correct
2	Correct	0 ms	348 KB	Output is correct
3	Correct	0 ms	424 KB	Output is correct
4	Correct	0 ms	348 KB	Output is correct
5	Correct	0 ms	348 KB	Output is correct
6	Correct	0 ms	348 KB	Output is correct
7	Correct	0 ms	348 KB	Output is correct
8	Correct	0 ms	348 KB	Output is correct
9	Correct	0 ms	348 KB	Output is correct
10	Correct	0 ms	348 KB	Output is correct
11	Correct	0 ms	348 KB	Output is correct
12	Correct	0 ms	348 KB	Output is correct
13	Correct	0 ms	348 KB	Output is correct
14	Correct	0 ms	348 KB	Output is correct
15	Correct	0 ms	348 KB	Output is correct
16	Correct	0 ms	348 KB	Output is correct
17	Correct	0 ms	600 KB	Output is correct
18	Correct	0 ms	348 KB	Output is correct
19	Correct	0 ms	348 KB	Output is correct
20	Correct	0 ms	348 KB	Output is correct
21	Correct	0 ms	348 KB	Output is correct
22	Correct	0 ms	348 KB	Output is correct
23	Correct	2 ms	600 KB	Output is correct
24	Correct	2 ms	604 KB	Output is correct
25	Correct	2 ms	600 KB	Output is correct
26	Correct	3 ms	1244 KB	Output is correct
27	Correct	3 ms	1116 KB	Output is correct
28	Correct	3 ms	1116 KB	Output is correct
29	Correct	3 ms	1116 KB	Output is correct
30	Correct	4 ms	1116 KB	Output is correct
31	Correct	3 ms	1628 KB	Output is correct

Subtask #4
43.0 / 43.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	344 KB	Output is correct
2	Correct	0 ms	348 KB	Output is correct
3	Correct	0 ms	424 KB	Output is correct
4	Correct	0 ms	348 KB	Output is correct
5	Correct	0 ms	348 KB	Output is correct
6	Correct	0 ms	348 KB	Output is correct
7	Correct	0 ms	348 KB	Output is correct
8	Correct	0 ms	348 KB	Output is correct
9	Correct	0 ms	348 KB	Output is correct
10	Correct	0 ms	348 KB	Output is correct
11	Correct	0 ms	348 KB	Output is correct
12	Correct	0 ms	348 KB	Output is correct
13	Correct	0 ms	348 KB	Output is correct
14	Correct	0 ms	348 KB	Output is correct
15	Correct	0 ms	348 KB	Output is correct
16	Correct	0 ms	348 KB	Output is correct
17	Correct	0 ms	600 KB	Output is correct
18	Correct	0 ms	348 KB	Output is correct
19	Correct	0 ms	348 KB	Output is correct
20	Correct	0 ms	348 KB	Output is correct
21	Correct	0 ms	348 KB	Output is correct
22	Correct	0 ms	348 KB	Output is correct
23	Correct	2 ms	600 KB	Output is correct
24	Correct	2 ms	604 KB	Output is correct
25	Correct	2 ms	600 KB	Output is correct
26	Correct	3 ms	1244 KB	Output is correct
27	Correct	3 ms	1116 KB	Output is correct
28	Correct	3 ms	1116 KB	Output is correct
29	Correct	3 ms	1116 KB	Output is correct
30	Correct	4 ms	1116 KB	Output is correct
31	Correct	3 ms	1628 KB	Output is correct
32	Correct	16 ms	4188 KB	Output is correct
33	Correct	16 ms	4188 KB	Output is correct
34	Correct	16 ms	4184 KB	Output is correct
35	Correct	88 ms	15640 KB	Output is correct
36	Correct	84 ms	15764 KB	Output is correct
37	Correct	94 ms	15696 KB	Output is correct
38	Correct	62 ms	16064 KB	Output is correct
39	Correct	64 ms	15928 KB	Output is correct
40	Correct	74 ms	16228 KB	Output is correct
41	Correct	101 ms	20180 KB	Output is correct

Submission #879510

Compilation message

Subtask #1 13.0 / 13.0

Subtask #2 15.0 / 15.0

Subtask #3 29.0 / 29.0

Subtask #4 43.0 / 43.0

Subtask #1
13.0 / 13.0

Subtask #2
15.0 / 15.0

Subtask #3
29.0 / 29.0

Subtask #4
43.0 / 43.0