Submission #363487

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Source Code Expand

#include<iostream>
#include<fstream>
#include<sstream>
#include<string>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<ctime>
#include<stack>
#include<queue>
#include<set>
#include<map>
#include<vector>
#include<list>
#include<algorithm>
#include<utility>
#include<complex>

using namespace std;

#define reE(i,a,b) for(auto (i)=(a);(i)<=(b);(i)++)
#define rE(i,b) reE(i,0,b)
#define reT(i,a,b) for(auto (i)=(a);(i)<(b);(i)++)
#define rT(i,b) reT(i,0,b)
#define rep(i,a,b) reE(i,a,b);
#define rev(i,a,b) for(auto (i)=(b)-1;(i)>=(a);(i)--)
#define itr(i,b) for(auto (i)=(b).begin();(i)!=(b).end();++(i))
#define rti(i,b) for(auto (i)=(b).rbegin();(i)!=(b).rend();++(i))
#define LL long long
#define all(b) (b).begin(),(b).end()

#define input_init stringstream ss; string strtoken, token; istringstream is
#define input_line  getline(cin, strtoken);is.str(strtoken);is.clear(istringstream::goodbit)
#define input_token(num) ss.str(""); ss.clear(stringstream::goodbit); getline(is, token, ','); ss << token; ss >> num

#define dir(xx,yy,x,y,i) (xx)=(x)+dir[(i)],(yy)=(y)+dir[(i)+1]

typedef complex<double> P;
typedef vector<P> Poly;

const LL INF = 1 << 30;
const double eps = 1e-9;
const int dir[] = { 0, 1, 0, -1, 0 };
inline double dot(const P a, const  P b){//A dot B
	return a.real()*b.real() + a.imag()*b.imag();
}

inline double cross(const P a, const P b){//A cross B

	return a.real()*b.imag() - a.imag()*b.real();
}



struct dynamic_convex{
	double priority;
	P xy;
	dynamic_convex(double p, P _xy){
		priority = p;
		xy = _xy;
	}

	bool operator>( const dynamic_convex &another)const{ return(priority > another.priority); }
	bool operator>=(const  dynamic_convex &another)const{ return(priority >= another.priority); }
	bool operator<(const dynamic_convex &another)const{ return(priority < another.priority); }
	bool operator<=(const  dynamic_convex &another)const{ return(priority <= another.priority); }
	bool operator==(const  dynamic_convex &another)const{ return(priority == another.priority); }
	bool operator!=(const  dynamic_convex &another)const{ return(priority != another.priority); }
};


template <class T>
struct avl_tree {
	struct node {
		T key;
		int size, height;
		node *child[2];
		node(const T &key) : key(key), size(1), height(1) {
			child[0] = child[1] = 0;
		}
	} *root;
	typedef node *pointer;
	avl_tree() { root = NULL; }

	pointer find(const T &key) { return find(root, key); }
	node *find(node *t, const T &key) {
		if (t == NULL) return NULL;
		if (key == t->key) return t;
		else if (key < t->key) return find(t->child[0], key);
		else                   return find(t->child[1], key);
	}
	void insert(const T &key) { root = insert(root, new node(key)); }
	node *insert(node *t, node *x) {
		if (t == NULL) return x;
		if (x->key <= t->key) t->child[0] = insert(t->child[0], x);
		else                  t->child[1] = insert(t->child[1], x);
		t->size += 1;
		return balance(t);
	}
	void erase(const T &key) { root = erase(root, key); }
	node *erase(node *t,const T &x) {
		if (t == NULL) return NULL;
		if (t->key==x) {
			return move_down(t->child[0], t->child[1]);
		}
		else {
			if (x < t->key) t->child[0] = erase(t->child[0], x);
			else            t->child[1] = erase(t->child[1], x);
			t->size -= 1;
			return balance(t);
		}
	}
	node *move_down(node *t, node *rhs) {
		if (t == NULL) return rhs;
		t->child[1] = move_down(t->child[1], rhs);
		return balance(t);
	}
#define sz(t) (t ? t->size : 0)
#define ht(t) (t ? t->height : 0)
	node *rotate(node *t, int l, int r) {
		node *s = t->child[r];
		t->child[r] = s->child[l];
		s->child[l] = balance(t);
		if (t) t->size = sz(t->child[0]) + sz(t->child[1]) + 1;
		if (s) s->size = sz(s->child[0]) + sz(s->child[1]) + 1;
		return balance(s);
	}
	node *balance(node *t) {
		for (int i = 0; i < 2; ++i) {
			if (ht(t->child[!i]) - ht(t->child[i]) < -1) {
				if (ht(t->child[i]->child[!i]) - ht(t->child[i]->child[i]) > 0)
					t->child[i] = rotate(t->child[i], i, !i);
				return rotate(t, !i, i);
			}
		}
		if (t) t->height = max(ht(t->child[0]), ht(t->child[1])) + 1;
		if (t) t->size = sz(t->child[0]) + sz(t->child[1]) + 1;
		return t;
	}
	pointer rank(int k) const { return rank(root, k); }
	pointer rank(node *t, int k) const {
		if (!t) return NULL;
		int m = sz(t->child[0]);
		if (k  < m) return rank(t->child[0], k);
		if (k == m) return t;
		return rank(t->child[1], k - m - 1);
	}
	T &operator[](int index){
		return rank(index)->key;
	}
};


typedef avl_tree<dynamic_convex> DC;
const double divi = 1 << 15;

#define rs(x) (x).root->size
bool dc_in(DC& t,P &p){
	if (t.root == NULL)return false;
	if (rs(t) == 1)return (t[0].xy == p);
	if (rs(t) == 2)return(abs(t[0].xy - p) + abs(t[1].xy - p) - abs(t[0].xy - t[1].xy) < eps);
	int a = 0, b = rs(t), c;
	double A, C;
	const P g = (t[a].xy + t[b - 1].xy + t[b / 2].xy) / 3.0;
	while (b - a > 1){
		c = (a + b) / 2;
		A = cross(t[a].xy - g, p - t[a].xy);
		C = cross(t[c].xy - g, p - t[c].xy);
		if (cross(t[a].xy - g, t[c].xy - g) > -eps){
			if (A>-eps&&C < -eps)b = c;
			else a = c;
		}
		else {
			if (C < -eps || A > -eps)b = c;
			else a = c;
		}
	}
	return(cross(t[b%rs(t)].xy - t[a].xy, p - t[b%rs(t)].xy) > -eps);
}
#define ix(i) (rs(t)+(i))%rs(t)
void dc_hull(DC &t, P &p){
	if (t.root == NULL){ t.insert(dynamic_convex(0, p)); return; }
	if (rs(t) == 1){ if (t.root->key.xy != p)t.insert(dynamic_convex(1, p)); return; }
	if (rs(t) == 2){
		double j = cross(t[1].xy - t[0].xy, p - t[1].xy);
		if (j > eps)t.insert(dynamic_convex(2, p));
		else if (j < -eps)t.insert(dynamic_convex(0.5, p));
		else{
			j = abs(t[0].xy - t[1].xy);
			double f = abs(t[0].xy - p), k = abs(p - t[1].xy);
			if (f - k > eps&&f - j > eps)t[1].xy = p;
			else if (f + k - j > eps)t[0].xy = p;
		}
		return;
	}
	int a = 0, b = rs(t), c;
	double A, C;
	const P g = (t[a].xy + t[b - 1].xy + t[b / 2].xy) / 3.0;
	while (b - a > 1){
		c = (a + b) / 2;
		A = cross(t[a].xy - g, p - t[a].xy);
		C = cross(t[c].xy - g, p - t[c].xy);
		if (cross(t[a].xy - g, t[c].xy - g) > -eps){
			if (A > -eps&&C < -eps)b = c;
			else a = c;
		}
		else {
			if (C < -eps || A > -eps)b = c;
			else a = c;
		}
	}
	if (cross(t[b%rs(t)].xy - t[a].xy, p - t[b%rs(t)].xy) > -eps)return;

	while (cross(t[ix(a)].xy - t[ix(a - 1)].xy, p - t[ix(a)].xy)<-eps){
		t.erase(t[ix(a)]); a=ix(a-1); b=a+1;
	}
	while (cross(t[ix(b)].xy - p, t[ix(b + 1)].xy - t[ix(b)].xy)<-eps)
		if (b == rs(t)){t.erase(t[ix(b)]); a=ix(a-1); b=a+1; }
		else
			t.erase(t[ix(b)]);

	double tmp;
	if (ix(b) == 0)tmp = t[ix(a)].priority + 1.0;
	else tmp = (t[ix(a)].priority + t[ix(b)].priority) / 2.0;
	t.insert(dynamic_convex(tmp, p));
}

DC dc;
//ofstream fout("output.txt");
int main(){
	int N;
	string s;
	double x, y;
	cin >> N;
	rT(i,N){
		cin >> s >> x >> y;
		//x /= divi;
		//y /= divi;
		P p(x, y);
		if (s == "MONITOR"){
			dc_hull(dc, p);
		}
		else{
	//		cout << p << endl;
			if (dc_in(dc, p))cout << "DANGER" << endl;
			else cout << "SAFE" << endl;
		}
	//	if (dc.root != NULL){ rT(i, rs(dc))cout << dc[i].xy; cout << endl; }
	}
	return(0);
}
/*
5
MONITOR 0 0
MONITOR 2 2
MONITOR 0 2
MONITOR 2 0
TARGET  2 2


*/

Submission Info

Judge Result