Submission #289148

#	Time	Username	Problem	Language	Result	Execution time	Memory
289148		tonowak	Dragon 2 (JOI17_dragon2)	C++14	15 / 100	4080 ms	6904 KiB

dragon2

#include "bits/stdc++.h" // Tomasz Nowak
using namespace std;     // XIII LO Szczecin
using LL = long long;    // Poland
#define FOR(i, l, r) for(int i = (l); i <= (r); ++i)
#define REP(i, n) FOR(i, 0, (n) - 1)
template<class T> int size(T &&x) {
	return int(x.size());
}
template<class A, class B> ostream& operator<<(ostream &out, const pair<A, B> &p) {
	return out << '(' << p.first << ", " << p.second << ')';
}
template<class T> auto operator<<(ostream &out, T &&x) -> decltype(x.begin(), out) {
	out << '{';
	for(auto it = x.begin(); it != x.end(); ++it)
		out << *it << (it == prev(x.end()) ? "" : ", ");
	return out << '}';
}
void dump() {}
template<class T, class... Args> void dump(T &&x, Args... args) {
	cerr << x << ";  ";
	dump(args...);
}
#ifdef DEBUG
  struct Nl{~Nl(){cerr << '\n';}};
# define debug(x...) cerr << (strcmp(#x, "") ? #x ":  " : ""), dump(x), Nl(), cerr << ""
#else
# define debug(...) 0 && cerr
#endif
mt19937_64 rng(0);
int rd(int l, int r) {
	return uniform_int_distribution<int>(l, r)(rng);
}
// end of templates

using P = pair<int, int>;
LL operator*(P a, P b) {
	return a.first * LL(b.second) - a.second * LL(b.first);
}
P operator-(P a, P b) {
	return {a.first - b.first, a.second - b.second};
}
int sign(LL x) {
	return x < 0 ? -1 : x > 0 ? 1 : 0;
}
LL dir(P a, P b, P c) {
	return (b - a) * (c - b);
}

P human1, human2;

bool intersects(P a, P b) {
	// debug(a, b);
	if(sign(dir(a, human1, b)) == sign(dir(a, human2, b)))
		return false;
	LL h1ah2 = dir(human1, a, human2),
	   h1bh2 = dir(human1, b, human2);
	// debug(h1ah2, h1bh2);
	if(sign(h1ah2) == sign(h1bh2)) {
		if(abs(h1ah2) < abs(h1bh2))
			return false;
	}
	return true;
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);

	int n, m;
	cin >> n >> m;
	vector<vector<P>> points(m);
	REP(i, n) {
		int x, y, c;
		cin >> x >> y >> c;
		points[--c].emplace_back(x, y);
	}
	cin >> human1.first >> human1.second >> human2.first >> human2.second;
	debug(points);
	debug(human1, human2);

	map<pair<int, int>, int> answers;
	int q;
	cin >> q;
	while(q --> 0) {
		int f, g;
		cin >> f >> g;
		--f, --g;
		if(answers.find(make_pair(f, g)) != answers.end()) {
			cout << answers[make_pair(f, g)] << '\n';
			continue;
		}

		int ret = 0;
		for(P p1 : points[f])
			for(P p2 : points[g]) {
				bool got = intersects(p1, p2);
				debug(p1, p2, got);
				ret += got;
			}
		cout << (answers[make_pair(f, g)] = ret) << '\n';
	}
}

• Subtask 1: 15 / 15
• Subtask 2: 0 / 45
• Subtask 3: 0 / 40