Submission #878637

#	Time	Username	Problem	Language	Result	Execution time	Memory
878637		marvinthang	Palembang Bridges (APIO15_bridge)	C++17	0 / 100	1 ms	460 KiB

bridge

/*************************************
*    author: marvinthang             *
*    created: 25.11.2023 08:57:19    *
*************************************/

#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

struct Median {
	long long sum = 0;
	priority_queue <int> left;
	priority_queue <int, vector <int>, greater <int>> right;
	void insert(int x) {
		if (left.empty() || x <= left.top()) {
			sum -= x;
			left.push(x);
			if (left.size() + 1 > right.size()) {
				x = left.top();
				left.pop();
				right.push(x);
				sum += 2 * x;
			}
		} else {
			sum += x;
			right.push(x);
			if (right.size() > left.size()) {
				x = right.top();
				right.pop();
				left.push(x);
				sum -= 2 * x;
			}
		}
	}
};

const long long INF = 1e18;

void process(void) {
	int k, n; cin >> k >> n;
	vector <pair <int, int>> segments;
	long long res = 0;
	REP(i, n) {
		char p, q; int s, t; cin >> p >> s >> q >> t;
		if (s > t) swap(s, t);
		if (p == q) res += t - s;
		else {
			++res;
			segments.emplace_back(s, t);
		}
	}
	if (segments.empty()) return void(cout << res << '\n');
	sort(ALL(segments), [&] (auto a, auto b) { return a.fi + a.se < b.fi + b.se; });
	Median med;
	n = segments.size();
	vector <long long> pref(n + 1);
	REP(i, n) {
		med.insert(segments[i].fi);
		med.insert(segments[i].se);
		pref[i + 1] = med.sum;
	}
	long long ans = pref[n];
	if (k == 2) {
		med = Median();
		REPD(i, n) {
			med.insert(segments[i].fi);
			med.insert(segments[i].se);
			minimize(ans, pref[i] + med.sum);
		}
	}
	cout << res + ans << '\n';
}

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

Compilation message (stderr)

bridge.cpp: In function 'int main()':
bridge.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); }
      |                                                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
bridge.cpp:113:2: note: in expansion of macro 'file'
  113 |  file("bridge");
      |  ^~~~
bridge.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); }
      |                                                                                       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
bridge.cpp:113:2: note: in expansion of macro 'file'
  113 |  file("bridge");
      |  ^~~~

• Subtask 1: 0 / 8
• Subtask 2: 0 / 14
• Subtask 3: 0 / 9
• Subtask 4: 0 / 32
• Subtask 5: 0 / 37