Submission #783103

---

Source Code Expand

#include<bits/stdc++.h>
#define rep(i,n) for(int i=0;i<(int)n;i++)
#define all(c) (c).begin(),(c).end()
#define mp make_pair
#define pb push_back
#define dbg(...) do{cerr<<__LINE__<<": ";dbgprint(#__VA_ARGS__, __VA_ARGS__);}while(0);

using namespace std;

namespace std{template<class S,class T>struct hash<pair<S,T>>{size_t operator()(const pair<S,T>&p)const{return ((size_t)1e9+7)*hash<S>()(p.first)+hash<T>()(p.second);}};template<class T>struct hash<vector<T>>{size_t operator()(const vector<T> &v)const{size_t h=0;for(auto i : v)h=h*((size_t)1e9+7)+hash<T>()(i)+1;return h;}};}
template<class T>ostream& operator<<(ostream &os, const vector<T> &v){os<<"[ ";rep(i,v.size())os<<v[i]<<(i==v.size()-1?" ]":", ");return os;}template<class T>ostream& operator<<(ostream &os,const set<T> &v){os<<"{ "; for(const auto &i:v)os<<i<<", ";return os<<"}";}
template<class T,class U>ostream& operator<<(ostream &os,const map<T,U> &v){os<<"{";for(const auto &i:v)os<<" "<<i.first<<": "<<i.second<<",";return os<<"}";}template<class T,class U>ostream& operator<<(ostream &os,const pair<T,U> &p){return os<<"("<<p.first<<", "<<p.second<<")";}
void dbgprint(const string &fmt){cerr<<endl;}template<class H,class... T>void dbgprint(const string &fmt,const H &h,const T&... r){cerr<<fmt.substr(0,fmt.find(","))<<"= "<<h<<" ";dbgprint(fmt.substr(fmt.find(",")+1),r...);}
typedef long long ll;typedef vector<int> vi;typedef pair<int,int> pi;const int inf = (int)1e9;const double INF = 1e12, EPS = 1e-9, PI = acos(-1.0);
typedef complex<double> P;
namespace std{
	bool operator<(const P& a, const P& b){
		return real(a) != real(b) ? real(a) < real(b) : imag(a) < imag(b);
	}
}
typedef vector<P> G;
inline int xor128(){
	//static int w = (unsigned int)time(NULL);
	static int w = 88675123;
	static int x = 123456789, y = 362436069, z = 521288629;
	int t = x ^ x << 11;
	x = y; y = z; z = w;
	return w = w ^ w >> 19 ^ t ^ t >> 8;
}
inline double cross(const P& a, const P& b){ return imag(conj(a)*b); }
inline double dot(const P& a, const P& b){ return real(conj(a)*b); }
struct L : public vector<P>{
	L(const P &a, const P &b) {
		push_back(a); push_back(b);
	}
};
inline int ccw(P a, P b, P c) {
	b -= a; c -= a;
	if(cross(b, c) > 0)   return +1;		// counter clockwise
	if(cross(b, c) < 0)   return -1;		// clockwise
	if(dot(b, c) < 0)     return +2;		// c--a--b on line
	if(norm(b) < norm(c)) return -2;		// a--b--c on line
	return 0;
}
G convex_hull(G ps) {
  int n = ps.size(), k = 0;
  sort(ps.begin(), ps.end());
  G ch(2*n);
  for (int i = 0; i < n; ch[k++] = ps[i++]) // lower-hull
    while (k >= 2 && ccw(ch[k-2], ch[k-1], ps[i]) <= 0) --k;
  for (int i = n-2, t = k+1; i >= 0; ch[k++] = ps[i--]) // upper-hull
    while (k >= t && ccw(ch[k-2], ch[k-1], ps[i]) <= 0) --k;
  ch.resize(k-1);
  return ch;
}

G input; int call = 0;
#if 0
inline double in(double x){
	call++;
	double mx = -INF; P r(cos(x), sin(x));
	for(P p : input){ mx = max(mx, imag(p * r)); }
	return mx;
}
#else
inline double in(double x){ printf("? %.12f\n", x*180/PI); fflush(stdout); double ymax; scanf("%lf", &ymax); return ymax; }
#endif

inline P solve(double t1, double y1, double t2, double y2){
	double c1 = cos(t1), c2 = cos(t2);
	double s1 = sin(t1), s2 = sin(t2);
	if((s1 * c2 - s2 * c1) == 0) return P(INF, INF);
	double x = (c2 * y1 - c1 * y2) / (s1 * c2 - s2 * c1);
	double y = (s2 * y1 - s1 * y2) / (c1 * s2 - c2 * s1);
	return P(x, y);
}

bool search(double t, P &res, const G &g, bool debug = 0){
	double y = in(t), delta = 0.1;
	if(y < EPS) return 0;
	
	rep(it, 10){
		double tt = t + delta, yy = in(tt), ycheck;
		P p = solve(t, y, tt, yy), p2;
		
		if(debug) dbg(p);
		
		if(!(abs(p.real()) < 1001 && abs(p.imag()) < 1001)) goto NEXT;
		p2 = p;
		p.real((int)round(p.real()));
		p.imag((int)round(p.imag()));
		if(debug) dbg(p, p2, abs(abs(p - p2)) > EPS, abs(abs(p - p2)));
		
		if(abs(abs(p - p2)) > 1e-5) goto NEXT;
		rep(i, g.size()) if(abs(g[i] - p) < EPS) goto NEXT;
		
		res = p;
		return 1;
		
		NEXT:
		delta /= 5;
	}
	return 0;
}

G run(){
	G g({P(0)});
	set<P> use;
	P p;
	if(!search(PI + 0.01, p, g)){
		search(PI + 0.01, p, g, 1);
		dbg(input); P r(cos(PI+0.01), sin(PI+0.01));
		for(P p : input) dbg(p * r);
		assert(0);
	}
	g.pb(p);
	int n = g.size();
	
	while(1){
		bool update = 0;
		rep(i, n) if(!use.count(g[i])){
			P res;
			double a = -arg(g[(i + 1) % n] - g[i]);
			
			if(search(a, res, g)){
				g.pb(res);
				update = 1;
				n++;
				break;
			}
			else if(search(a + PI, res, g)){
				g.pb(res);
				update = 1;
				n++;
				break;
			}
			else use.insert(g[i]);
		}
		sort(all(g), [](P a, P b){ return abs(a) < EPS || abs(b) < EPS ? abs(a) < abs(b) : arg(a) < arg(b);});
		if(!update) break;
	}
	return g;
}

int main(){
	#if 1
	{
		G g = run(); int n = g.size();
		printf("! %d\n", n);
		rep(i, n) printf("! %d %d\n", (int)(real(g[i])), (int)(imag(g[i]))); fflush(stdout);
	}
	#else
	rep(it, 1000){
		int n = xor128() % 1000 + 10;
		G g;
		rep(i, n){
			int x = xor128() % 2001 - 1000;
			int y = -(xor128() % 1000 + 1);
			g.pb(P(x, y));
		}
		g.pb(P(0));
		g = convex_hull(g);
		input = g; call = 0;
		
		G res = run();
		sort(all(g)); sort(all(res));
		if(g != res){
			dbg(it, g.size(), res.size());
			dbg(g); dbg(res);
			//assert(0);
		}
	}
	#endif
	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘double in(double)’:
./Main.cpp:66:108: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
 inline double in(double x){ printf("? %.12f\n", x*180/PI); fflush(stdout); double ymax; scanf("%lf", &ymax); return ymax; }
                                                                                                            ^

Judge Result