답안 #90504

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
90504 2018-12-22T03:24:48 Z jasony123123 Kosta (COI14_kosta) C++11
48 / 100
5000 ms 27264 KB
#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
//#include <ext/pb_ds/tree_policy.hpp>
//#include <ext/pb_ds/assoc_container.hpp>
using namespace std;
//using namespace __gnu_pbds;

#define FOR(i,start,end) for(int i=start;i<(int)(end);i++)
#define FORE(i,start,end) for(int i=start;i<=(int)end;i++)
#define RFOR(i,start,end) for(int i = start; i>end; i--)
#define RFORE(i,start,end) for(int i = start; i>=end; i--)
#define all(a) a.begin(), a.end()
#define mt make_tuple
#define mp make_pair
#define v vector
#define sf scanf
#define pf printf
#define dvar(x) cout << #x << " := " << x << "\n"
#define darr(x,n) FOR(i,0,n) cout << #x << "[" << i << "]" << " := " << x[i] << "\n"

typedef long long ll;
typedef long double ld;
typedef pair<int, int > pii;
typedef pair<ll, ll> pll;
//template <class T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template<class T> void minn(T &a, T b) { a = min(a, b); }
template<class T> void maxx(T &a, T b) { a = max(a, b); }

void io() {
#ifdef LOCAL_PROJECT 
	freopen("input.in", "r", stdin); freopen("output.out", "w", stdout);
#else 
	/* online submission */

#endif 
	ios_base::sync_with_stdio(false); cin.tie(NULL);
}

const ll MOD = 1000000007LL;
const ll PRIME = 105943LL;
const int INF = 1e8;
/****************************************************************/
/*
Find minimum D st K points with boxes of 2D sides cover all points
*/

struct BBox {
	int x1, y1, x2, y2;
	BBox() {
		x1 = INF, y1 = INF, x2 = -INF, y2 = -INF;
	}
	void upd(pii a) {
		minn(x1, a.first);
		maxx(x2, a.first);
		minn(y1, a.second);
		maxx(y2, a.second);
	}
	void upd(BBox b) {
		minn(x1, b.x1);
		minn(y1, b.y1);
		maxx(x2, b.x2);
		maxx(y2, b.y2);
	}
};

struct Event {// f: {0, point} {1,box left/bot} {2, box right, top} 
	int p, f, idx;
	Event(int a, int b, int c) {
		p = a, f = b, idx = c;
	}
	inline bool operator<(const Event &b) const {
		return p < b.p;
	}
};

const int MAXN = 200000;
int K, N;
pii pnts[MAXN];

BBox rem[MAXN];
int cnt[4000000];
void add(int x, int y, int val) {
	x += 2e6;
	y += 2e6;
	FORE(i, x, y)
		cnt[i] += val;
}
int query(int x) {
	x += 2e6;
	return cnt[x];
}

void reset() {
	fill(rem, rem + N, BBox());
	fill(cnt, cnt + 4000000, 0);
}

void sweep(int pFlag, int bFlag, v<Event> &lst) {
	BBox cur;
	FOR(i, 0, lst.size()) {
		v<int> curidx[3];
		int pc = lst[i].p;
		curidx[lst[i].f].push_back(lst[i].idx);
		while (i + 1 < lst.size() && lst[i + 1].p == pc) {
			i++;
			curidx[lst[i].f].push_back(lst[i].idx);
		}

		// process boxes first, then points
		for (int b : curidx[bFlag])
			rem[b].upd(cur);
		for (int p : curidx[pFlag])
			cur.upd(pnts[p]);
	}
}

void initRemBox(int d) {
	v<Event> lstX, lstY;
	FOR(i, 0, N) {
		lstX.push_back(Event(pnts[i].first, 0, i));
		lstX.push_back(Event(pnts[i].first - d, 1, i));
		lstX.push_back(Event(pnts[i].first + d, 2, i));
		lstY.push_back(Event(pnts[i].second, 0, i));
		lstY.push_back(Event(pnts[i].second - d, 1, i));
		lstY.push_back(Event(pnts[i].second + d, 2, i));
	}
	sort(all(lstX));
	sweep(0, 1, lstX);
	reverse(all(lstX));
	sweep(0, 2, lstX);
	sort(all(lstY));
	sweep(0, 1, lstY);
	reverse(all(lstY));
	sweep(0, 2, lstY);
}

BBox toNeeded(BBox b, int d) {
	BBox ans;
	ans.x1 = b.x2 - d;
	ans.x2 = b.x1 + d;
	ans.y1 = b.y2 - d;
	ans.y2 = b.y1 + d;
	return ans;
}

bool isOk(BBox b) {
	return b.x1 <= b.x2 && b.y1 <= b.y2;
}

pii works(int d) {
	initRemBox(d);
	v<Event> lst;
	FOR(i, 0, N) {
		if (rem[i].x1 == INF && rem[i].x2 == -INF) {
			return{ i, i };
		}
		rem[i] = toNeeded(rem[i], d);
		if (isOk(rem[i])) {
			lst.push_back(Event(rem[i].x1, 1, i));
			lst.push_back(Event(rem[i].x2, 2, i));
		}
		lst.push_back(Event(pnts[i].first, 0, i));
	}
	// see if exists a point inside of a box BIT+reverse lookup
	sort(all(lst));
	FOR(i, 0, lst.size()) {
		v<int> curidx[3];
		int pc = lst[i].p;
		curidx[lst[i].f].push_back(lst[i].idx);
		while (i + 1 < lst.size() && lst[i + 1].p == pc) {
			i++;
			curidx[lst[i].f].push_back(lst[i].idx);
		}

		for (int b : curidx[1]) // starting
			add(rem[b].y1, rem[b].y2, 1);
		for (int p : curidx[0]) {// points
			if (query(pnts[p].second) > 0) { // this point(p) is inside something
				RFORE(j, i, 0) if (lst[j].f == 1) {
					int b = lst[j].idx;
					if (rem[b].y1 <= pnts[p].second && pnts[p].second <= rem[b].y2) {
						return{ b,p };
					}
				}
				assert(0);
			}
		}
		for (int b : curidx[2]) // ending
			add(rem[b].y1, rem[b].y2, -1);
	}
	return{ -1,-1 };
}

void solve2() {
	pii ans;
	int lo = 0, hi = 2e6 + 1;	
	while (lo<hi) {
		int mid = (hi + lo) / 2;

		reset();
		ans = works(mid);
		
		if (ans == mp(-1, -1)) {
			lo = mid + 1;
		}
		else {
			hi = mid;
		}
	}
	ans = works(lo);
	cout << lo << "\n" << ans.first + 1 << " " << ans.second + 1 << "\n";
}

void solve1() {
	BBox b;
	FOR(i, 0, N) b.upd(pnts[i]);
	pii ans = { INF, -1 };
	FOR(i, 0, N) {
		int d = max(max(abs(b.x1 - pnts[i].first), abs(b.x2 - pnts[i].first)), max(abs(b.y1 - pnts[i].second), abs(b.y2 - pnts[i].second)));
		minn(ans, { d,i });
	}
	cout << ans.first << "\n" << ans.second + 1 << "\n";
}
int main() {
	io();
	cin >> K >> N;
	BBox entire;
	FOR(i, 0, N) {
		int x, y;
		cin >> x >> y;
		pnts[i].first = x + y;
		pnts[i].second = x - y;
		entire.upd(pnts[i]);
	}
	FOR(i, 0, N) {
		pnts[i].first -= entire.x1;
		pnts[i].second -= entire.y1;
	}

	if (K == 1) solve1();
	else solve2();

	return 0;
}

Compilation message

kosta.cpp: In function 'void sweep(int, int, std::vector<Event>&)':
kosta.cpp:104:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   while (i + 1 < lst.size() && lst[i + 1].p == pc) {
          ~~~~~~^~~~~~~~~~~~
kosta.cpp: In function 'pii works(int)':
kosta.cpp:170:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   while (i + 1 < lst.size() && lst[i + 1].p == pc) {
          ~~~~~~^~~~~~~~~~~~
# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 3452 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 3580 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 29 ms 4648 KB Output is correct
2 Correct 28 ms 4648 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 43 ms 5076 KB Output is correct
2 Correct 46 ms 5360 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 62 ms 19248 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 84 ms 19376 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 254 ms 19816 KB Output is correct
2 Correct 701 ms 20020 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 174 ms 20020 KB Output is correct
2 Correct 183 ms 20092 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 1334 ms 25044 KB Output is correct
2 Execution timed out 5105 ms 25324 KB Time limit exceeded
3 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Execution timed out 5010 ms 27264 KB Time limit exceeded
2 Halted 0 ms 0 KB -