Submission #875999

#	Time	Username	Problem	Language	Result	Execution time	Memory
875999		marvinthang	Circle selection (APIO18_circle_selection)	C++17	100 / 100	882 ms	70796 KiB

circle_selection

/*************************************
*    author: marvinthang             *
*    created: 21.11.2023 10:16:16    *
*************************************/

#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 << '}'; }

// end of template

const int INF = 1e9;

struct Circle {
	int x, y, r, idx;
	Circle(int x, int y, int r, int idx): x(x), y(y), r(r), idx(idx) {}
	bool operator < (const Circle &ot) { return pair {r, ot.idx} > pair {ot.r, idx}; }
};

void process(void) {
	int n; cin >> n;
	vector <Circle> circles;
	int min_x = INF, min_y = INF, max_x = 0;
	REP(i, n) {
		int x, y, r; cin >> x >> y >> r;
		circles.emplace_back(x, y, r, i);
		min_x = min(min_x, x);
		min_y = min(min_y, y);
		max_x = max(max_x, x);
	}
	vector <vector <pair <int, int>>> List(1);
	REP(i, n) {
		circles[i].x -= min_x;
		circles[i].y -= min_y;
	}
	sort(ALL(circles));
	REP(i, n) List[0].emplace_back(circles[i].y, i);
	sort(ALL(List[0]));
	int lg = __lg(max_x - min_x) + 1;
	vector <int> res(n, -1);
	auto sqr = [&] (int x) {
		return 1LL * x * x;
	};
	auto intersection = [&] (int i, int j) {
		return sqr(circles[i].x - circles[j].x) + sqr(circles[i].y - circles[j].y) <= sqr(circles[i].r + circles[j].r);
	};
	REP(i, n) if (res[circles[i].idx] < 0) {
		while (lg && circles[i].r <= MASK(lg - 1)) {
			--lg;
			vector <vector <pair <int, int>>> new_list;
			for (auto List: List) {
				vector <vector <pair <int, int>>> cur(2);
				for (auto v: List) if (res[circles[v.se].idx] < 0) cur[(circles[v.se].x >> lg) & 1].push_back(v);
				REP(i, 2) if (!cur[i].empty()) new_list.push_back(cur[i]);
			}
			List = move(new_list);
		}
		auto cmp = [&] (const vector <pair <int, int>> &a, const int &x) { 
			return (circles[a[0].se].x >> lg) < x; 
		};
		for (auto it = lower_bound(ALL(List), (circles[i].x >> lg) - 2, cmp); it != List.end() && cmp(*it, (circles[i].x >> lg) + 3); ++it) {
			for (auto p = lower_bound(ALL(*it), circles[i].y - 2LL * circles[i].r, [&] (const pair <int, int> &a, const long long &x) { return a.fi < x; }); p != it->end() && p->fi <= circles[i].y + 2LL * circles[i].r; ++p) 
				if (res[circles[p->se].idx] < 0 && intersection(p->se, i)) res[circles[p->se].idx] = circles[i].idx;
		}

	}
	REP(i, n) cout << res[i] + 1 << ' ';
}

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

Compilation message (stderr)

circle_selection.cpp: In function 'int main()':
circle_selection.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); }
      |                                                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
circle_selection.cpp:105:2: note: in expansion of macro 'file'
  105 |  file("circle_selection");
      |  ^~~~
circle_selection.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); }
      |                                                                                       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
circle_selection.cpp:105:2: note: in expansion of macro 'file'
  105 |  file("circle_selection");
      |  ^~~~

• Subtask 1: 7 / 7
• Subtask 2: 12 / 12
• Subtask 3: 15 / 15
• Subtask 4: 23 / 23
• Subtask 5: 30 / 30
• Subtask 6: 13 / 13