Submission #882959

#	Time	Username	Problem	Language	Result	Execution time	Memory
882959		marvinthang	Constellation 3 (JOI20_constellation3)	C++17	100 / 100	330 ms	67404 KiB

constellation3

/*************************************
*    author: marvinthang             *
*    created: 04.12.2023 16:03:56    *
*************************************/

#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 << '}'; }

// index from 0
template <class T> struct Fenwick {
    int n; vector <T> bit;
    Fenwick(int _n = 0): n(_n), bit(n + 1, 0) {}
    void reset(void) { fill(bit.begin(), bit.end(), 0); }
    void resize(int _n) { bit.assign(_n + 1, 0); }
    void update(int i, T val) { for (++i; i <= n; i += i & -i) bit[i] += val; }
    T get(int i) {
        if (i < 0) return 0;
        T res(0);
        for (i = min(i + 1, n); i > 0; i &= i - 1) res += bit[i];
        return res;
    }
    int upper_bound(T val) {
        int res = 0;
        for (int i = __lg(n); i >= 0; --i) 
            if ((res | MASK(i)) <= n && val >= bit[res | MASK(i)]) res |= MASK(i), val -= bit[res];
        return res;
    }
    int lower_bound(T val) {
        int res = 0;
        for (int i = __lg(n); i >= 0; --i)
            if ((res | MASK(i)) <= n && val > bit[res | MASK(i)]) res |= MASK(i), val -= bit[res];
        return res;
    }
};

// end of template

const int LOG = 18;

void process(void) {
	int n; cin >> n;
	vector <int> a(n);
	stack <int> st;
	vector <array <int, LOG>> anc(n);
	REP(i, n) {
		cin >> a[i];
		int last = -1;
		while (!st.empty() && a[st.top()] < a[i]) {
			last = st.top();
			st.pop();
		}
		if (!st.empty()) anc[i][0] = st.top();
		else anc[i][0] = i;
		if (last != -1) anc[last][0] = i;
		st.push(i);
	}
	vector <vector <int>> adj(n);
	int rt = -1;
	REP(i, n) {
		if (anc[i][0] == i) rt = i;
		else adj[anc[i][0]].push_back(i);
	}
	vector <int> depth(n), tin(n), tout(n);
	int t = 0;
	function<void(int)> dfs = [&] (int u) {
		tin[u] = t++;
		FOR(i, 1, LOG) anc[u][i] = anc[anc[u][i - 1]][i - 1];
		for (int v: adj[u]) {
			depth[v] = depth[u] + 1;
			dfs(v);
		}
		tout[u] = t;
	};
	dfs(rt);
	int m; cin >> m;
	vector <vector <pair <int, int>>> stars(n);
	long long sum = 0;
	while (m--) {
		int x, y, c; cin >> x >> y >> c; --x;
		sum += c;
		int u = x;
		REPD(i, LOG) if (a[anc[u][i]] < y) u = anc[u][i];
		stars[u].emplace_back(x, c);
	}
	Fenwick <long long> bit(n);
	vector <long long> dp(n), sum_dp(n);
	function<void(int)> dfs2 = [&] (int u) {
		for (int v: adj[u]) {
			dfs2(v);
			sum_dp[u] += dp[v];
		}
		if ((int) adj[u].size() == 2) {
			REP(t, 2) {
				bit.update(tin[adj[u][t]], dp[adj[u][!t]]);
				bit.update(tout[adj[u][t]], -dp[adj[u][!t]]);
			}
		}
		dp[u] = sum_dp[u];
		for (auto [x, c]: stars[u]) {
			dp[u] = max(dp[u], bit.get(tin[x]) + c + sum_dp[x]);
		}
	};
	dfs2(rt);
	cout << sum - dp[rt] << '\n';
}

int main(void) {
	ios_base::sync_with_stdio(false); cin.tie(nullptr); // cout.tie(nullptr);
	file("JOI20_constellation3");
	// int t; cin >> t; while (t--)
	process();
	// cerr << "Time elapsed: " << TIME << " s.\n";
	return (0^0);
}

Compilation message (stderr)

constellation3.cpp: In function 'int main()':
constellation3.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); }
      |                                                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
constellation3.cpp:143:2: note: in expansion of macro 'file'
  143 |  file("JOI20_constellation3");
      |  ^~~~
constellation3.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); }
      |                                                                                       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
constellation3.cpp:143:2: note: in expansion of macro 'file'
  143 |  file("JOI20_constellation3");
      |  ^~~~

• Subtask 1: 14 / 14
• Subtask 2: 21 / 21
• Subtask 3: 65 / 65