oj.uz

Submission #879509

# Submission time Handle Problem Language Result Execution time Memory
879509 2023-11-27T15:09:43 Z marvinthang Beads and wires (APIO14_beads) C++17
100 / 100
 123 ms 26820 KB 
/*************************************
*    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 long long INF = 1e10 + 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 <long long, 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 <long long, long long> best_child(-INF, -INF);
		for (auto [w, v]: adj[u]) {
			long long 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 Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 600 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 544 KB Output is correct
12 Correct 0 ms 344 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 600 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 544 KB Output is correct
12 Correct 0 ms 344 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 1 ms 348 KB Output is correct
18 Correct 1 ms 348 KB Output is correct
19 Correct 1 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 1 ms 348 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 600 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 544 KB Output is correct
12 Correct 0 ms 344 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 1 ms 348 KB Output is correct
18 Correct 1 ms 348 KB Output is correct
19 Correct 1 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 1 ms 348 KB Output is correct
23 Correct 2 ms 860 KB Output is correct
24 Correct 2 ms 860 KB Output is correct
25 Correct 2 ms 860 KB Output is correct
26 Correct 3 ms 1372 KB Output is correct
27 Correct 4 ms 1372 KB Output is correct
28 Correct 4 ms 1368 KB Output is correct
29 Correct 4 ms 1372 KB Output is correct
30 Correct 3 ms 1372 KB Output is correct
31 Correct 4 ms 1624 KB Output is correct

Subtask #4
43.0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 600 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 544 KB Output is correct
12 Correct 0 ms 344 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 1 ms 348 KB Output is correct
18 Correct 1 ms 348 KB Output is correct
19 Correct 1 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 1 ms 348 KB Output is correct
23 Correct 2 ms 860 KB Output is correct
24 Correct 2 ms 860 KB Output is correct
25 Correct 2 ms 860 KB Output is correct
26 Correct 3 ms 1372 KB Output is correct
27 Correct 4 ms 1372 KB Output is correct
28 Correct 4 ms 1368 KB Output is correct
29 Correct 4 ms 1372 KB Output is correct
30 Correct 3 ms 1372 KB Output is correct
31 Correct 4 ms 1624 KB Output is correct
32 Correct 17 ms 4956 KB Output is correct
33 Correct 17 ms 5004 KB Output is correct
34 Correct 16 ms 4956 KB Output is correct
35 Correct 84 ms 18808 KB Output is correct
36 Correct 123 ms 18732 KB Output is correct
37 Correct 89 ms 18892 KB Output is correct
38 Correct 66 ms 19140 KB Output is correct
39 Correct 68 ms 22796 KB Output is correct
40 Correct 69 ms 22460 KB Output is correct
41 Correct 95 ms 26820 KB Output is correct