Brief description:
Problem D. Hall of Mirrors
给定一个镜中世界.. . 问点光源处有多少束光线可以在 D 射程内反射回来。
( D <= 50,镜子只有水平和竖直两种.. .)
Analysis:
比赛的时候写的是发射扇形的区间。。。并在反射过程中不断细分细分。。。
(仍然有待实现。。)
看了代码发现很多人利用运动的相对性。。将平面沿着镜面的反射方向进行平铺。。。
这样处理后可以保证光束自始自终是一条直线。。。。其实上述思路的真正意义是对解进行离散化。。。
(裸计算几何方法比较无脑。。小数据大概都要跑 7 分钟吧。。还有一些恶心的精度问题。。)
(。。。)
/** ` Micro Mezzo Macro Flation -- Overheated Economy ., **/ #include <algorithm> #include <iostream> #include <iomanip> #include <sstream> #include <cstring> #include <cstdio> #include <string> #include <vector> #include <bitset> #include <queue> #include <stack> #include <cmath> #include <ctime> #include <list> #include <set> #include <map> using namespace std; #define REP(i, n) for (int i=0;i<int(n);++i) #define FOR(i, a, b) for (int i=int(a);i<int(b);++i) #define DWN(i, b, a) for (int i=int(b-1);i>=int(a);--i) #define REP_1(i, n) for (int i=1;i<=int(n);++i) #define FOR_1(i, a, b) for (int i=int(a);i<=int(b);++i) #define DWN_1(i, b, a) for (int i=int(b);i>=int(a);--i) #define REP_C(i, n) for (int n____=int(n),i=0;i<n____;++i) #define FOR_C(i, a, b) for (int b____=int(b),i=a;i<b____;++i) #define DWN_C(i, b, a) for (int a____=int(a),i=b-1;i>=a____;--i) #define REP_N(i, n) for (i=0;i<int(n);++i) #define FOR_N(i, a, b) for (i=int(a);i<int(b);++i) #define DWN_N(i, b, a) for (i=int(b-1);i>=int(a);--i) #define REP_1_C(i, n) for (int n____=int(n),i=1;i<=n____;++i) #define FOR_1_C(i, a, b) for (int b____=int(b),i=a;i<=b____;++i) #define DWN_1_C(i, b, a) for (int a____=int(a),i=b;i>=a____;--i) #define REP_1_N(i, n) for (i=1;i<=int(n);++i) #define FOR_1_N(i, a, b) for (i=int(a);i<=int(b);++i) #define DWN_1_N(i, b, a) for (i=int(b);i>=int(a);--i) #define REP_C_N(i, n) for (n____=int(n),i=0;i<n____;++i) #define FOR_C_N(i, a, b) for (b____=int(b),i=a;i<b____;++i) #define DWN_C_N(i, b, a) for (a____=int(a),i=b-1;i>=a____;--i) #define REP_1_C_N(i, n) for (n____=int(n),i=1;i<=n____;++i) #define FOR_1_C_N(i, a, b) for (b____=int(b),i=a;i<=b____;++i) #define DWN_1_C_N(i, b, a) for (a____=int(a),i=b;i>=a____;--i) #define ECH(it, A) for (typeof(A.begin()) it=A.begin(); it != A.end(); ++it) #define DO(n) while(n--) #define DO_C(n) int n____ = n; while(n____--) #define TO(i, a, b) int s_=a<b?1:-1,b_=b+s_;for(int i=a;i!=b_;i+=s_) #define TO_1(i, a, b) int s_=a<b?1:-1,b_=b;for(int i=a;i!=b_;i+=s_) #define SQZ(i, j, a, b) for (int i=int(a),j=int(b)-1;i<j;++i,--j) #define SQZ_1(i, j, a, b) for (int i=int(a),j=int(b);i<=j;++i,--j) #define REP_2(i, j, n, m) REP(i, n) REP(j, m) #define REP_2_1(i, j, n, m) REP_1(i, n) REP_1(j, m) #define ALL(A) A.begin(), A.end() #define LLA(A) A.rbegin(), A.rend() #define CPY(A, B) memcpy(A, B, sizeof(A)) #define INS(A, P, B) A.insert(A.begin() + P, B) #define ERS(A, P) A.erase(A.begin() + P) #define BSC(A, X) find(ALL(A), X) // != A.end() #define CTN(T, x) (T.find(x) != T.end()) #define SZ(A) int(A.size()) #define PB push_back #define MP(A, B) make_pair(A, B) #define Rush int T____; RD(T____); DO(T____) #pragma comment(linker, "/STACK:36777216") //#pragma GCC optimize ("O2") #define Ruby system("ruby main.rb") #define Haskell system("runghc main.hs") #define Pascal system("fpc main.pas") typedef long long LL; typedef double DB; typedef unsigned UINT; typedef unsigned long long ULL; typedef vector<int> VI; typedef vector<char> VC; typedef vector<string> VS; typedef vector<LL> VL; typedef vector<DB> VD; typedef set<int> SI; typedef set<string> SS; typedef set<LL> SL; typedef set<DB> SD; typedef map<int, int> MII; typedef map<string, int> MSI; typedef map<LL, int> MLI; typedef map<DB, int> MDI; typedef map<int, bool> MIB; typedef map<string, bool> MSB; typedef map<LL, bool> MLB; typedef map<DB, bool> MDB; typedef pair<int, int> PII; typedef pair<int, bool> PIB; typedef vector<PII> VII; typedef vector<VI> VVI; typedef vector<VII> VVII; typedef set<PII> SII; typedef map<PII, int> MPIII; typedef map<PII, bool> MPIIB; /** I/O Accelerator **/ /* ... :" We are I/O Accelerator ... Use us at your own risk ;) ... " .. */ template<class T> inline void RD(T &); template<class T> inline void OT(const T &); inline int RD(){ int x; RD(x); return x;} template<class T> inline T& _RD(T &x){ RD(x); return x;} inline void RC(char &c){scanf(" %c", &c);} inline void RS(char *s){scanf("%s", s);} template<class T0, class T1> inline void RD(T0 &x0, T1 &x1){RD(x0), RD(x1);} template<class T0, class T1, class T2> inline void RD(T0 &x0, T1 &x1, T2 &x2){RD(x0), RD(x1), RD(x2);} template<class T0, class T1, class T2, class T3> inline void RD(T0 &x0, T1 &x1, T2 &x2, T3 &x3){RD(x0), RD(x1), RD(x2), RD(x3);} template<class T0, class T1, class T2, class T3, class T4> inline void RD(T0 &x0, T1 &x1, T2 &x2, T3 &x3, T4 &x4){RD(x0), RD(x1), RD(x2), RD(x3), RD(x4);} template<class T0, class T1, class T2, class T3, class T4, class T5> inline void RD(T0 &x0, T1 &x1, T2 &x2, T3 &x3, T4 &x4, T5 &x5){RD(x0), RD(x1), RD(x2), RD(x3), RD(x4), RD(x5);} template<class T0, class T1, class T2, class T3, class T4, class T5, class T6> inline void RD(T0 &x0, T1 &x1, T2 &x2, T3 &x3, T4 &x4, T5 &x5, T6 &x6){RD(x0), RD(x1), RD(x2), RD(x3), RD(x4), RD(x5), RD(x6);} template<class T0, class T1> inline void OT(T0 &x0, T1 &x1){OT(x0), OT(x1);} template<class T0, class T1, class T2> inline void OT(T0 &x0, T1 &x1, T2 &x2){OT(x0), OT(x1), OT(x2);} template<class T0, class T1, class T2, class T3> inline void OT(T0 &x0, T1 &x1, T2 &x2, T3 &x3){OT(x0), OT(x1), OT(x2), OT(x3);} template<class T0, class T1, class T2, class T3, class T4> inline void OT(T0 &x0, T1 &x1, T2 &x2, T3 &x3, T4 &x4){OT(x0), OT(x1), OT(x2), OT(x3), OT(x4);} template<class T0, class T1, class T2, class T3, class T4, class T5> inline void OT(T0 &x0, T1 &x1, T2 &x2, T3 &x3, T4 &x4, T5 &x5){OT(x0), OT(x1), OT(x2), OT(x3), OT(x4), OT(x5);} template<class T0, class T1, class T2, class T3, class T4, class T5, class T6> inline void OT(T0 &x0, T1 &x1, T2 &x2, T3 &x3, T4 &x4, T5 &x5, T6 &x6){OT(x0), OT(x1), OT(x2), OT(x3), OT(x4), OT(x5), OT(x6);} template<class T> inline void RST(T &A){memset(A, 0, sizeof(A));} template<class T0, class T1> inline void RST(T0 &A0, T1 &A1){RST(A0), RST(A1);} template<class T0, class T1, class T2> inline void RST(T0 &A0, T1 &A1, T2 &A2){RST(A0), RST(A1), RST(A2);} template<class T0, class T1, class T2, class T3> inline void RST(T0 &A0, T1 &A1, T2 &A2, T3 &A3){RST(A0), RST(A1), RST(A2), RST(A3);} template<class T0, class T1, class T2, class T3, class T4> inline void RST(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4){RST(A0), RST(A1), RST(A2), RST(A3), RST(A4);} template<class T0, class T1, class T2, class T3, class T4, class T5> inline void RST(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5){RST(A0), RST(A1), RST(A2), RST(A3), RST(A4), RST(A5);} template<class T0, class T1, class T2, class T3, class T4, class T5, class T6> inline void RST(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5, T6 &A6){RST(A0), RST(A1), RST(A2), RST(A3), RST(A4), RST(A5), RST(A6);} template<class T> inline void CLR(T &A){A.clear();} template<class T0, class T1> inline void CLR(T0 &A0, T1 &A1){CLR(A0), CLR(A1);} template<class T0, class T1, class T2> inline void CLR(T0 &A0, T1 &A1, T2 &A2){CLR(A0), CLR(A1), CLR(A2);} template<class T0, class T1, class T2, class T3> inline void CLR(T0 &A0, T1 &A1, T2 &A2, T3 &A3){CLR(A0), CLR(A1), CLR(A2), CLR(A3);} template<class T0, class T1, class T2, class T3, class T4> inline void CLR(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4){CLR(A0), CLR(A1), CLR(A2), CLR(A3), CLR(A4);} template<class T0, class T1, class T2, class T3, class T4, class T5> inline void CLR(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5){CLR(A0), CLR(A1), CLR(A2), CLR(A3), CLR(A4), CLR(A5);} template<class T0, class T1, class T2, class T3, class T4, class T5, class T6> inline void CLR(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5, T6 &A6){CLR(A0), CLR(A1), CLR(A2), CLR(A3), CLR(A4), CLR(A5), CLR(A6);} template<class T> inline void CLR(T &A, int n){REP(i, n) CLR(A[i]);} template<class T> inline void FLC(T &A, int x){memset(A, x, sizeof(A));} template<class T0, class T1> inline void FLC(T0 &A0, T1 &A1, int x){FLC(A0, x), FLC(A1, x);} template<class T0, class T1, class T2> inline void FLC(T0 &A0, T1 &A1, T2 &A2){FLC(A0), FLC(A1), FLC(A2);} template<class T0, class T1, class T2, class T3> inline void FLC(T0 &A0, T1 &A1, T2 &A2, T3 &A3){FLC(A0), FLC(A1), FLC(A2), FLC(A3);} template<class T0, class T1, class T2, class T3, class T4> inline void FLC(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4){FLC(A0), FLC(A1), FLC(A2), FLC(A3), FLC(A4);} template<class T0, class T1, class T2, class T3, class T4, class T5> inline void FLC(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5){FLC(A0), FLC(A1), FLC(A2), FLC(A3), FLC(A4), FLC(A5);} template<class T0, class T1, class T2, class T3, class T4, class T5, class T6> inline void FLC(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5, T6 &A6){FLC(A0), FLC(A1), FLC(A2), FLC(A3), FLC(A4), FLC(A5), FLC(A6);} template<class T> inline void SRT(T &A){sort(ALL(A));} template<class T, class C> inline void SRT(T &A, C B){sort(ALL(A), B);} /** Add - On **/ const int MOD = 1000000007; const int INF = 10009; const DB EPS = 1e-9; const DB OO = 1e15; const DB PI = 3.14159265358979323846264;//M_PI; // <<= ` 0. Daily Use ., template<class T> inline void checkMin(T &a,const T b){if (b<a) a=b;} template<class T> inline void checkMax(T &a,const T b){if (b>a) a=b;} template <class T, class C> inline void checkMin(T& a, const T b, C c){if (c(b,a)) a = b;} template <class T, class C> inline void checkMax(T& a, const T b, C c){if (c(a,b)) a = b;} template<class T> inline T min(T a, T b, T c){return min(min(a, b), c);} template<class T> inline T max(T a, T b, T c){return max(max(a, b), c);} template<class T> inline T min(T a, T b, T c, T d){return min(min(a, b), min(c, d));} template<class T> inline T sqr(T a){return a*a;} template<class T> inline T cub(T a){return a*a*a;} int Ceil(int x, int y){return (x - 1) / y + 1;} // <<= ` 1. Bitwise Operation ., inline bool _1(int x, int i){return x & 1<<i;} inline int _1(int i){return 1<<i;} inline int _U(int i){return _1(i) - 1;}; inline int count_bits(int x){ x = (x & 0x55555555) + ((x & 0xaaaaaaaa) >> 1); x = (x & 0x33333333) + ((x & 0xcccccccc) >> 2); x = (x & 0x0f0f0f0f) + ((x & 0xf0f0f0f0) >> 4); x = (x & 0x00ff00ff) + ((x & 0xff00ff00) >> 8); x = (x & 0x0000ffff) + ((x & 0xffff0000) >> 16); return x; } template<class T> inline T low_bit(T x) { return x & -x; } template<class T> inline T high_bit(T x) { T p = low_bit(x); while (p != x) x -= p, p = low_bit(x); return p; } // <<= ` 2. Modular Arithmetic Basic ., inline void INC(int &a, int b){a += b; if (a >= MOD) a -= MOD;} inline int sum(int a, int b){a += b; if (a >= MOD) a -= MOD; return a;} inline void DEC(int &a, int b){a -= b; if (a < 0) a += MOD;} inline int dff(int a, int b){a -= b; if (a < 0) a += MOD; return a;} inline void MUL(int &a, int b){a = int((LL)a * b % MOD);} inline int pdt(int a, int b){return int((LL)a * b % MOD);} // <<= '9. Comutational Geometry ., struct Po; struct Line; struct Seg; inline int sgn(DB x){return x < -EPS ? -1 : x > EPS;} inline int sgn(DB x, DB y){return sgn(x - y);} struct Po{ DB x, y; Po(DB _x = 0, DB _y = 0):x(_x), y(_y){} friend istream& operator >>(istream& in, Po &p){return in >> p.x >> p.y;} friend ostream& operator <<(ostream& out, Po p){return out << "(" << p.x << ", " << p.y << ")";} friend bool operator ==(Po, Po); friend bool operator !=(Po, Po); friend Po operator +(Po, Po); friend Po operator -(Po, Po); friend Po operator *(Po, DB); friend Po operator /(Po, DB); bool operator < (const Po &rhs) const{return sgn(x, rhs.x) < 0 || sgn(x, rhs.x) == 0 && sgn(y, rhs.y) < 0;} Po& operator +=(Po rhs){x += rhs.x, y += rhs.y;} Po& operator -=(Po rhs){x -= rhs.x, y -= rhs.y;} Po& operator *=(DB k){x *= k, y *= k;} Po& operator /=(DB k){x /= k, y /= k;} DB length_sqr(){return sqr(x) + sqr(y);} DB length(){return sqrt(length_sqr());} DB atan(){ return atan2(y, x); } void input(){ int _x, _y; scanf("%d %d", &_x, &_y); x = _x, y = _y; } }; bool operator ==(Po a, Po b){return sgn(a.x - b.x) == 0 && sgn(a.y - b.y) == 0;} bool operator !=(Po a, Po b){return sgn(a.x - b.x) != 0 || sgn(a.y - b.y) != 0;} Po operator +(Po a, Po b){return Po(a.x + b.x, a.y + b.y);} Po operator -(Po a, Po b){return Po(a.x - b.x, a.y - b.y);} Po operator *(Po a, DB k){return Po(a.x * k, a.y * k);} Po operator /(Po a, DB k){return Po(a.x / k, a.y / k);} struct Line{ Po a, b; Line(Po _a = Po(), Po _b = Po()):a(_a), b(_b){} Line(DB x0, DB y0, DB x1, DB y1):a(Po(x0, y0)), b(Po(x1, y1)){} Line(Seg); friend ostream& operator <<(ostream& out, Line p){return out << p.a << "-" << p.b;} }; struct Seg{ Po a, b; Seg(Po _a = Po(), Po _b = Po()):a(_a), b(_b){} Seg(DB x0, DB y0, DB x1, DB y1):a(Po(x0, y0)), b(Po(x1, y1)){} Seg(Line l); friend ostream& operator <<(ostream& out, Seg p){return out << p.a << "-" << p.b;} DB length(){return (b - a).length();} }; Line::Line(Seg l):a(l.a), b(l.b){} Seg::Seg(Line l):a(l.a), b(l.b){} #define innerProduct dot #define scalarProduct dot #define dotProduct dot #define outerProduct det #define crossProduct det inline DB dot(DB x1, DB y1, DB x2, DB y2){return x1 * x2 + y1 * y2;} inline DB dot(Po a, Po b){return dot(a.x, b.y, b.x, b.y);} inline DB dot(Po p0, Po p1, Po p2){return dot(p1 - p0, p2 - p0);} inline DB dot(Line l1, Line l2){return dot(l1.b - l1.a, l2.b - l2.a);} inline DB det(DB x1, DB y1, DB x2, DB y2){return x1 * y2 - x2 * y1;} inline DB det(Po a, Po b){return det(a.x, a.y, b.x, b.y);} inline DB det(Po p0, Po p1, Po p2){return det(p1 - p0, p2 - p0);} inline DB det(Line l1, Line l2){return det(l1.b - l1.a, l2.b - l2.a);} template<class T1, class T2> inline DB dist(T1 x, T2 y){return sqrt(dist_sqr(x, y));} inline DB dist_sqr(Po a, Po b){return sqr(a.x - b.x) + sqr(a.y - b.y);} inline DB dist_sqr(Po p, Line l){Po v0 = l.b - l.a, v1 = p - l.a; return sqr(fabs(det(v0, v1))) / v0.length_sqr();} inline DB dist_sqr(Po p, Seg l){ Po v0 = l.b - l.a, v1 = p - l.a, v2 = p - l.b; if (sgn(dot(v0, v1)) * sgn(dot(v0, v2)) <= 0) return dist_sqr(p, Line(l)); else return min(v1.length_sqr(), v2.length_sqr()); } inline DB dist_sqr(Line l, Po p){ return dist_sqr(p, l); } inline DB dist_sqr(Line l1, Line l2){ if (sgn(det(l1, l2)) != 0) return 0; return dist_sqr(l1.a, l2); } inline DB dist_sqr(Line l1, Seg l2){ Po v0 = l1.b - l1.a, v1 = l2.a - l1.a, v2 = l2.b - l1.a; DB c1 = det(v0, v1), c2 = det(v0, v2); return sgn(c1) != sgn(c2) ? 0 : sqr(min(fabs(c1), fabs(c2))) / v0.length_sqr(); } inline DB dist_sqr(Seg l, Po p){ return dist_sqr(p, l); } inline DB dist_sqr(Seg l1, Line l2){ return dist_sqr(l2, l1); } bool isIntersect(Seg l1, Seg l2){ //if (l1.a == l2.a || l1.a == l2.b || l1.b == l2.a || l1.b == l2.b) return true; return min(l1.a.x, l1.b.x) <= max(l2.a.x, l2.b.x) && min(l2.a.x, l2.b.x) <= max(l1.a.x, l1.b.x) && min(l1.a.y, l1.b.y) <= max(l2.a.y, l2.b.y) && min(l2.a.y, l2.b.y) <= max(l1.a.y, l1.b.y) && sgn( det(l1.a, l2.a, l2.b) ) * sgn( det(l1.b, l2.a, l2.b) ) <= 0 && sgn( det(l2.a, l1.a, l1.b) ) * sgn( det(l2.b, l1.a, l1.b) ) <= 0; } inline DB dist_sqr(Seg l1, Seg l2){ if (isIntersect(l1, l2)) return 0; else return min(dist_sqr(l1.a, l2), dist_sqr(l1.b, l2), dist_sqr(l2.a, l1), dist_sqr(l2.b, l1)); } inline bool isOnExtremePoint(const Po &p, const Seg &l){ return p == l.a || p == l.b; } inline bool isOnseg(const Po &p, const Seg &l){ //if (p == l.a || p == l.b) return false; return sgn(det(p, l.a, l.b)) == 0 && sgn(l.a.x, p.x) * sgn(l.b.x, p.x) <= 0 && sgn(l.a.y, p.y) * sgn(l.b.y, p.y) <= 0; } inline Po intersect(const Line &l1, const Line &l2){ return l1.a + (l1.b - l1.a) * (det(l2.a, l1.a, l2.b) / det(l2, l1)); } // perpendicular foot inline Po intersect(const Po & p, const Line &l){ return intersect(Line(p, p + Po(l.a.y - l.b.y, l.b.x - l.a.x)), l); } inline Po rotate(Po p, DB alpha, Po o = Po()){ p.x -= o.x, p.y -= o .y; return Po(p.x * cos(alpha) - p.y * sin(alpha), p.y * cos(alpha) + p.x * sin(alpha)) + o; } // <<= ' 0. I/O Accelerator interface ., template<class T> inline void RD(T &x){ //cin >> x; scanf("%d", &x); //char c; for (c = getchar(); c < '0'; c = getchar()); x = c - '0'; for (c = getchar(); c >= '0'; c = getchar()) x = x * 10 + c - '0'; //char c; c = getchar(); x = c - '0'; for (c = getchar(); c >= '0'; c = getchar()) x = x * 10 + c - '0'; } int ____Case; template<class T> inline void OT(const T &x){ printf("Case #%d: ", ++____Case); printf("%d", x); puts(""); } /* .................................................................................................................................. */ const int N = 39; char Map[N][N], tmp[N][N]; int n, m, D, X0, Y0, res; vector<Line> mirror; struct ray{ Po p; int dx, dy; ray(){} ray(Po _p, int _dx, int _dy):p(_p), dx(_dx), dy(_dy){} Po p_(){ return Po(p.x + 2e2*dx, p.y + 2e2*dy); } } cur; vector<pair<Po, bool> > L; vector<DB> P; DB _d, d; Po O; inline Po lb(int x, int y){ return Po(x * 2 + 2, y * 2); } inline Po rb(int x, int y){ return Po(x * 2 + 2, y * 2 + 2); } inline Po lu(int x, int y){ return Po(x * 2, y * 2); } inline Po ru(int x, int y){ return Po(x * 2, y * 2 + 2); } inline Po mm(int x, int y){ return Po(x * 2 + 1, y * 2 + 1); } void init(){ RST(Map); CLR(mirror); RD(n, m, D); d = D * 2; REP_2(i, j, n, m){ RC(Map[i][j]); if (Map[i][j] == 'X') X0 = i, Y0 = j, Map[i][j] = '.'; } int _i, _j; CPY(tmp, Map); REP_2(i, j, n, m) if (tmp[i][j] == '#'){ _j = j, tmp[i][j] = '.'; while (tmp[i][j+1] == '#'){ tmp[i][++j] = '.'; } mirror.PB(Line(lb(i, _j), rb(i, j))); mirror.PB(Line(lu(i, _j), ru(i, j))); } CPY(tmp, Map); REP_2(j, i, m, n) if (tmp[i][j] == '#'){ _i = i, tmp[i][j] = '.'; while (tmp[i+1][j] == '#'){ tmp[++i][j] = '.'; } mirror.PB(Line(lu(_i, j), lb(i, j))); mirror.PB(Line(ru(_i, j), rb(i, j))); } /* REP(i, SZ(mirror)){ cout << mirror[i] << endl; } cout << "----" << endl; */ O = mm(X0, Y0), res = 0; } bool comp(pair<Po, bool> a, pair<Po, bool> b){ return dist_sqr(cur.p, a.first) <= dist_sqr(cur.p, b.first); } int main(){ freopen("D-large-practice.in", "r", stdin); //freopen("in.txt", "r", stdin); freopen("out.txt", "w", stdout); Rush{ init(); FOR_1(i, -D, D) FOR_1(j, -D, D){ if (!i && abs(j) != 1) continue; if (!j && abs(i) != 1) continue; if (i && j && abs(__gcd(i, j)) != 1) continue; if (sqr(i)+sqr(j) > sqr(D)) continue; cur = ray(O, i, j), _d = 0; while (true){ Line l = Line(cur.p, cur.p_()); CLR(L, P); REP(ii, SZ(mirror)) if (!isOnseg(cur.p, mirror[ii])){ Po p = intersect(l, mirror[ii]); if (isOnseg(p, l)){ if (isOnExtremePoint(p, mirror[ii])) P.PB(dist_sqr(cur.p, p)); else if (isOnseg(p, mirror[ii])) L.PB(MP(p, !sgn(mirror[ii].a.x, mirror[ii].b.x))); } } sort(ALL(L), comp), SRT(P); if (!P.empty() && sgn(P[0], dist_sqr(cur.p, L[0].first)) < 0){ bool bx = false, by = false; REP(ii, SZ(mirror)) if (!isOnseg(cur.p, mirror[ii])){ Po p = intersect(l, mirror[ii]); if (isOnseg(p, l)){ if (isOnExtremePoint(p, mirror[ii])){ if (!sgn(dist_sqr(cur.p, p), P[0])){ if (!sgn(mirror[ii].a.x, mirror[ii].b.x)){ if ( (min(mirror[ii].a.y, mirror[ii].b.y) == p.y) ^ (j<0) ) by = true; } else { if ( (min(mirror[ii].a.x, mirror[ii].b.x) == p.x) ^ (i<0) ) bx = true; } } } } if (bx && by) break; } if (bx && by) break; } if (cur.p != O && isOnseg(O, l) && dist_sqr(cur.p, O) < dist_sqr(cur.p, L[0].first)){ if ( sgn(_d + dist(cur.p, O), d) <= 0) ++res; break; } _d += dist(cur.p, L[0].first); if (sgn(_d, d) >= 0) break; cur.p = L[0].first; if (SZ(L) >= 2 && !sgn(dist(cur.p, L[0].first) , dist(cur.p, L[1].first))){ cur.dx = -cur.dx, cur.dy = -cur.dy; } else { if (L[0].second) cur.dx = -cur.dx; else cur.dy = -cur.dy; } } } OT(res); cerr << "Case: " << ____Case << endl; } }
/** ` Micro Mezzo Macro Flation -- Overheated Economy ., **/ #include <algorithm> #include <iostream> #include <iomanip> #include <sstream> #include <cstring> #include <cstdio> #include <string> #include <vector> #include <bitset> #include <queue> #include <stack> #include <cmath> #include <ctime> #include <list> #include <set> #include <map> using namespace std; #define REP(i, n) for (int i=0;i<int(n);++i) #define FOR(i, a, b) for (int i=int(a);i<int(b);++i) #define DWN(i, b, a) for (int i=int(b-1);i>=int(a);--i) #define REP_1(i, n) for (int i=1;i<=int(n);++i) #define FOR_1(i, a, b) for (int i=int(a);i<=int(b);++i) #define DWN_1(i, b, a) for (int i=int(b);i>=int(a);--i) #define REP_C(i, n) for (int n____=int(n),i=0;i<n____;++i) #define FOR_C(i, a, b) for (int b____=int(b),i=a;i<b____;++i) #define DWN_C(i, b, a) for (int a____=int(a),i=b-1;i>=a____;--i) #define REP_N(i, n) for (i=0;i<int(n);++i) #define FOR_N(i, a, b) for (i=int(a);i<int(b);++i) #define DWN_N(i, b, a) for (i=int(b-1);i>=int(a);--i) #define REP_1_C(i, n) for (int n____=int(n),i=1;i<=n____;++i) #define FOR_1_C(i, a, b) for (int b____=int(b),i=a;i<=b____;++i) #define DWN_1_C(i, b, a) for (int a____=int(a),i=b;i>=a____;--i) #define REP_1_N(i, n) for (i=1;i<=int(n);++i) #define FOR_1_N(i, a, b) for (i=int(a);i<=int(b);++i) #define DWN_1_N(i, b, a) for (i=int(b);i>=int(a);--i) #define REP_C_N(i, n) for (n____=int(n),i=0;i<n____;++i) #define FOR_C_N(i, a, b) for (b____=int(b),i=a;i<b____;++i) #define DWN_C_N(i, b, a) for (a____=int(a),i=b-1;i>=a____;--i) #define REP_1_C_N(i, n) for (n____=int(n),i=1;i<=n____;++i) #define FOR_1_C_N(i, a, b) for (b____=int(b),i=a;i<=b____;++i) #define DWN_1_C_N(i, b, a) for (a____=int(a),i=b;i>=a____;--i) #define ECH(it, A) for (typeof(A.begin()) it=A.begin(); it != A.end(); ++it) #define DO(n) while(n--) #define DO_C(n) int n____ = n; while(n____--) #define TO(i, a, b) int s_=a<b?1:-1,b_=b+s_;for(int i=a;i!=b_;i+=s_) #define TO_1(i, a, b) int s_=a<b?1:-1,b_=b;for(int i=a;i!=b_;i+=s_) #define SQZ(i, j, a, b) for (int i=int(a),j=int(b)-1;i<j;++i,--j) #define SQZ_1(i, j, a, b) for (int i=int(a),j=int(b);i<=j;++i,--j) #define REP_2(i, j, n, m) REP(i, n) REP(j, m) #define REP_2_1(i, j, n, m) REP_1(i, n) REP_1(j, m) #define ALL(A) A.begin(), A.end() #define LLA(A) A.rbegin(), A.rend() #define CPY(A, B) memcpy(A, B, sizeof(A)) #define INS(A, P, B) A.insert(A.begin() + P, B) #define ERS(A, P) A.erase(A.begin() + P) #define BSC(A, X) find(ALL(A), X) // != A.end() #define CTN(T, x) (T.find(x) != T.end()) #define SZ(A) int(A.size()) #define PB push_back #define MP(A, B) make_pair(A, B) #define Rush int T____; RD(T____); DO(T____) #pragma comment(linker, "/STACK:36777216") //#pragma GCC optimize ("O2") #define Ruby system("ruby main.rb") #define Haskell system("runghc main.hs") #define Pascal system("fpc main.pas") typedef long long LL; typedef double DB; typedef unsigned UINT; typedef unsigned long long ULL; typedef vector<int> VI; typedef vector<char> VC; typedef vector<string> VS; typedef vector<LL> VL; typedef vector<DB> VD; typedef set<int> SI; typedef set<string> SS; typedef set<LL> SL; typedef set<DB> SD; typedef map<int, int> MII; typedef map<string, int> MSI; typedef map<LL, int> MLI; typedef map<DB, int> MDI; typedef map<int, bool> MIB; typedef map<string, bool> MSB; typedef map<LL, bool> MLB; typedef map<DB, bool> MDB; typedef pair<int, int> PII; typedef pair<int, bool> PIB; typedef vector<PII> VII; typedef vector<VI> VVI; typedef vector<VII> VVII; typedef set<PII> SII; typedef map<PII, int> MPIII; typedef map<PII, bool> MPIIB; /** I/O Accelerator **/ /* ... :" We are I/O Accelerator ... Use us at your own risk ;) ... " .. */ template<class T> inline void RD(T &); template<class T> inline void OT(const T &); inline int RD(){ int x; RD(x); return x;} template<class T> inline T& _RD(T &x){ RD(x); return x;} inline void RC(char &c){scanf(" %c", &c);} inline void RS(char *s){scanf("%s", s);} template<class T0, class T1> inline void RD(T0 &x0, T1 &x1){RD(x0), RD(x1);} template<class T0, class T1, class T2> inline void RD(T0 &x0, T1 &x1, T2 &x2){RD(x0), RD(x1), RD(x2);} template<class T0, class T1, class T2, class T3> inline void RD(T0 &x0, T1 &x1, T2 &x2, T3 &x3){RD(x0), RD(x1), RD(x2), RD(x3);} template<class T0, class T1, class T2, class T3, class T4> inline void RD(T0 &x0, T1 &x1, T2 &x2, T3 &x3, T4 &x4){RD(x0), RD(x1), RD(x2), RD(x3), RD(x4);} template<class T0, class T1, class T2, class T3, class T4, class T5> inline void RD(T0 &x0, T1 &x1, T2 &x2, T3 &x3, T4 &x4, T5 &x5){RD(x0), RD(x1), RD(x2), RD(x3), RD(x4), RD(x5);} template<class T0, class T1, class T2, class T3, class T4, class T5, class T6> inline void RD(T0 &x0, T1 &x1, T2 &x2, T3 &x3, T4 &x4, T5 &x5, T6 &x6){RD(x0), RD(x1), RD(x2), RD(x3), RD(x4), RD(x5), RD(x6);} template<class T0, class T1> inline void OT(T0 &x0, T1 &x1){OT(x0), OT(x1);} template<class T0, class T1, class T2> inline void OT(T0 &x0, T1 &x1, T2 &x2){OT(x0), OT(x1), OT(x2);} template<class T0, class T1, class T2, class T3> inline void OT(T0 &x0, T1 &x1, T2 &x2, T3 &x3){OT(x0), OT(x1), OT(x2), OT(x3);} template<class T0, class T1, class T2, class T3, class T4> inline void OT(T0 &x0, T1 &x1, T2 &x2, T3 &x3, T4 &x4){OT(x0), OT(x1), OT(x2), OT(x3), OT(x4);} template<class T0, class T1, class T2, class T3, class T4, class T5> inline void OT(T0 &x0, T1 &x1, T2 &x2, T3 &x3, T4 &x4, T5 &x5){OT(x0), OT(x1), OT(x2), OT(x3), OT(x4), OT(x5);} template<class T0, class T1, class T2, class T3, class T4, class T5, class T6> inline void OT(T0 &x0, T1 &x1, T2 &x2, T3 &x3, T4 &x4, T5 &x5, T6 &x6){OT(x0), OT(x1), OT(x2), OT(x3), OT(x4), OT(x5), OT(x6);} template<class T> inline void RST(T &A){memset(A, 0, sizeof(A));} template<class T0, class T1> inline void RST(T0 &A0, T1 &A1){RST(A0), RST(A1);} template<class T0, class T1, class T2> inline void RST(T0 &A0, T1 &A1, T2 &A2){RST(A0), RST(A1), RST(A2);} template<class T0, class T1, class T2, class T3> inline void RST(T0 &A0, T1 &A1, T2 &A2, T3 &A3){RST(A0), RST(A1), RST(A2), RST(A3);} template<class T0, class T1, class T2, class T3, class T4> inline void RST(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4){RST(A0), RST(A1), RST(A2), RST(A3), RST(A4);} template<class T0, class T1, class T2, class T3, class T4, class T5> inline void RST(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5){RST(A0), RST(A1), RST(A2), RST(A3), RST(A4), RST(A5);} template<class T0, class T1, class T2, class T3, class T4, class T5, class T6> inline void RST(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5, T6 &A6){RST(A0), RST(A1), RST(A2), RST(A3), RST(A4), RST(A5), RST(A6);} template<class T> inline void CLR(T &A){A.clear();} template<class T0, class T1> inline void CLR(T0 &A0, T1 &A1){CLR(A0), CLR(A1);} template<class T0, class T1, class T2> inline void CLR(T0 &A0, T1 &A1, T2 &A2){CLR(A0), CLR(A1), CLR(A2);} template<class T0, class T1, class T2, class T3> inline void CLR(T0 &A0, T1 &A1, T2 &A2, T3 &A3){CLR(A0), CLR(A1), CLR(A2), CLR(A3);} template<class T0, class T1, class T2, class T3, class T4> inline void CLR(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4){CLR(A0), CLR(A1), CLR(A2), CLR(A3), CLR(A4);} template<class T0, class T1, class T2, class T3, class T4, class T5> inline void CLR(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5){CLR(A0), CLR(A1), CLR(A2), CLR(A3), CLR(A4), CLR(A5);} template<class T0, class T1, class T2, class T3, class T4, class T5, class T6> inline void CLR(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5, T6 &A6){CLR(A0), CLR(A1), CLR(A2), CLR(A3), CLR(A4), CLR(A5), CLR(A6);} template<class T> inline void CLR(T &A, int n){REP(i, n) CLR(A[i]);} template<class T> inline void FLC(T &A, int x){memset(A, x, sizeof(A));} template<class T0, class T1> inline void FLC(T0 &A0, T1 &A1, int x){FLC(A0, x), FLC(A1, x);} template<class T0, class T1, class T2> inline void FLC(T0 &A0, T1 &A1, T2 &A2){FLC(A0), FLC(A1), FLC(A2);} template<class T0, class T1, class T2, class T3> inline void FLC(T0 &A0, T1 &A1, T2 &A2, T3 &A3){FLC(A0), FLC(A1), FLC(A2), FLC(A3);} template<class T0, class T1, class T2, class T3, class T4> inline void FLC(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4){FLC(A0), FLC(A1), FLC(A2), FLC(A3), FLC(A4);} template<class T0, class T1, class T2, class T3, class T4, class T5> inline void FLC(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5){FLC(A0), FLC(A1), FLC(A2), FLC(A3), FLC(A4), FLC(A5);} template<class T0, class T1, class T2, class T3, class T4, class T5, class T6> inline void FLC(T0 &A0, T1 &A1, T2 &A2, T3 &A3, T4 &A4, T5 &A5, T6 &A6){FLC(A0), FLC(A1), FLC(A2), FLC(A3), FLC(A4), FLC(A5), FLC(A6);} template<class T> inline void SRT(T &A){sort(ALL(A));} template<class T, class C> inline void SRT(T &A, C B){sort(ALL(A), B);} /** Add - On **/ const int MOD = 1000000007; const int INF = 0x7fffffff; const DB EPS = 1e-9; const DB OO = 1e15; const DB PI = 3.14159265358979323846264;//M_PI; // <<= ` 0. Daily Use ., template<class T> inline void checkMin(T &a,const T b){if (b<a) a=b;} template<class T> inline void checkMax(T &a,const T b){if (b>a) a=b;} template <class T, class C> inline void checkMin(T& a, const T b, C c){if (c(b,a)) a = b;} template <class T, class C> inline void checkMax(T& a, const T b, C c){if (c(a,b)) a = b;} template<class T> inline T min(T a, T b, T c){return min(min(a, b), c);} template<class T> inline T max(T a, T b, T c){return max(max(a, b), c);} template<class T> inline T min(T a, T b, T c, T d){return min(min(a, b), min(c, d));} template<class T> inline T sqr(T a){return a*a;} template<class T> inline T cub(T a){return a*a*a;} int Ceil(int x, int y){return (x - 1) / y + 1;} // <<= ` 1. Bitwise Operation ., inline bool _1(int x, int i){return x & 1<<i;} inline int _1(int i){return 1<<i;} inline int _U(int i){return _1(i) - 1;}; inline int count_bits(int x){ x = (x & 0x55555555) + ((x & 0xaaaaaaaa) >> 1); x = (x & 0x33333333) + ((x & 0xcccccccc) >> 2); x = (x & 0x0f0f0f0f) + ((x & 0xf0f0f0f0) >> 4); x = (x & 0x00ff00ff) + ((x & 0xff00ff00) >> 8); x = (x & 0x0000ffff) + ((x & 0xffff0000) >> 16); return x; } template<class T> inline T low_bit(T x) { return x & -x; } template<class T> inline T high_bit(T x) { T p = low_bit(x); while (p != x) x -= p, p = low_bit(x); return p; } // <<= '9. Comutational Geometry ., struct Po; struct Line; struct Seg; inline int sgn(DB x){return x < -EPS ? -1 : x > EPS;} inline int sgn(DB x, DB y){return sgn(x - y);} struct Po{ DB x, y; Po(DB _x = 0, DB _y = 0):x(_x), y(_y){} friend istream& operator >>(istream& in, Po &p){return in >> p.x >> p.y;} friend ostream& operator <<(ostream& out, Po p){return out << "(" << p.x << ", " << p.y << ")";} friend bool operator ==(Po, Po); friend Po operator +(Po, Po); friend Po operator -(Po, Po); friend Po operator *(Po, DB); friend Po operator /(Po, DB); bool operator < (const Po &rhs) const{return sgn(x, rhs.x) < 0 || sgn(x, rhs.x) == 0 && sgn(y, rhs.y) < 0;} Po& operator +=(Po rhs){x += rhs.x, y += rhs.y;} Po& operator -=(Po rhs){x -= rhs.x, y -= rhs.y;} Po& operator *=(DB k){x *= k, y *= k;} Po& operator /=(DB k){x /= k, y /= k;} DB length_sqr(){return sqr(x) + sqr(y);} DB length(){return sqrt(length_sqr());} DB atan(){ return atan2(y, x); } void input(){ int _x, _y; scanf("%d %d", &_x, &_y); x = _x, y = _y; } }; bool operator ==(Po a, Po b){return sgn(a.x - b.x) == 0 && sgn(a.y - b.y) == 0;} Po operator +(Po a, Po b){return Po(a.x + b.x, a.y + b.y);} Po operator -(Po a, Po b){return Po(a.x - b.x, a.y - b.y);} Po operator *(Po a, DB k){return Po(a.x * k, a.y * k);} Po operator /(Po a, DB k){return Po(a.x / k, a.y / k);} struct Line{ Po a, b; Line(Po _a = Po(), Po _b = Po()):a(_a), b(_b){} Line(DB x0, DB y0, DB x1, DB y1):a(Po(x0, y0)), b(Po(x1, y1)){} Line(Seg); }; struct Seg{ Po a, b; Seg(Po _a = Po(), Po _b = Po()):a(_a), b(_b){} Seg(DB x0, DB y0, DB x1, DB y1):a(Po(x0, y0)), b(Po(x1, y1)){} Seg(Line l); DB length(){return (b - a).length();} }; Line::Line(Seg l):a(l.a), b(l.b){} Seg::Seg(Line l):a(l.a), b(l.b){} #define innerProduct dot #define scalarProduct dot #define dotProduct dot #define outerProduct det #define crossProduct det inline DB dot(DB x1, DB y1, DB x2, DB y2){return x1 * x2 + y1 * y2;} inline DB dot(Po a, Po b){return dot(a.x, b.y, b.x, b.y);} inline DB dot(Po p0, Po p1, Po p2){return dot(p1 - p0, p2 - p0);} inline DB dot(Line l1, Line l2){return dot(l1.b - l1.a, l2.b - l2.a);} inline DB det(DB x1, DB y1, DB x2, DB y2){return x1 * y2 - x2 * y1;} inline DB det(Po a, Po b){return det(a.x, a.y, b.x, b.y);} inline DB det(Po p0, Po p1, Po p2){return det(p1 - p0, p2 - p0);} inline DB det(Line l1, Line l2){return det(l1.b - l1.a, l2.b - l2.a);} template<class T1, class T2> inline DB dist(T1 x, T2 y){return sqrt(dist_sqr(x, y));} inline DB dist_sqr(Po a, Po b){return sqr(a.x - b.x) + sqr(a.y - b.y);} inline DB dist_sqr(Po p, Line l){Po v0 = l.b - l.a, v1 = p - l.a; return sqr(fabs(det(v0, v1))) / v0.length_sqr();} inline DB dist_sqr(Po p, Seg l){ Po v0 = l.b - l.a, v1 = p - l.a, v2 = p - l.b; if (sgn(dot(v0, v1)) * sgn(dot(v0, v2)) <= 0) return dist_sqr(p, Line(l)); else return min(v1.length_sqr(), v2.length_sqr()); } inline DB dist_sqr(Line l, Po p){ return dist_sqr(p, l); } inline DB dist_sqr(Line l1, Line l2){ if (sgn(det(l1, l2)) != 0) return 0; return dist_sqr(l1.a, l2); } inline DB dist_sqr(Line l1, Seg l2){ Po v0 = l1.b - l1.a, v1 = l2.a - l1.a, v2 = l2.b - l1.a; DB c1 = det(v0, v1), c2 = det(v0, v2); return sgn(c1) != sgn(c2) ? 0 : sqr(min(fabs(c1), fabs(c2))) / v0.length_sqr(); } inline DB dist_sqr(Seg l, Po p){ return dist_sqr(p, l); } inline DB dist_sqr(Seg l1, Line l2){ return dist_sqr(l2, l1); } bool isIntersect(Seg l1, Seg l2){ //if (l1.a == l2.a || l1.a == l2.b || l1.b == l2.a || l1.b == l2.b) return true; return min(l1.a.x, l1.b.x) <= max(l2.a.x, l2.b.x) && min(l2.a.x, l2.b.x) <= max(l1.a.x, l1.b.x) && min(l1.a.y, l1.b.y) <= max(l2.a.y, l2.b.y) && min(l2.a.y, l2.b.y) <= max(l1.a.y, l1.b.y) && sgn( det(l1.a, l2.a, l2.b) ) * sgn( det(l1.b, l2.a, l2.b) ) <= 0 && sgn( det(l2.a, l1.a, l1.b) ) * sgn( det(l2.b, l1.a, l1.b) ) <= 0; } inline DB dist_sqr(Seg l1, Seg l2){ if (isIntersect(l1, l2)) return 0; else return min(dist_sqr(l1.a, l2), dist_sqr(l1.b, l2), dist_sqr(l2.a, l1), dist_sqr(l2.b, l1)); } inline bool isOnseg(const Po &p, const Seg &l){ return sgn(det(p, l.a, l.b)) == 0 && sgn(l.a.x, p.x) * sgn(l.b.x, p.x) <= 0 && sgn(l.a.y, p.y) * sgn(l.b.y, p.y) <= 0; } inline Po intersect(const Line &l1, const Line &l2){ return l1.a + (l1.b - l1.a) * (det(l2.a, l1.a, l2.b) / det(l2, l1)); } // perpendicular foot inline Po intersect(const Po & p, const Line &l){ return intersect(Line(p, p + Po(l.a.y - l.b.y, l.b.x - l.a.x)), l); } inline Po rotate(Po p, DB alpha, Po o = Po()){ p.x -= o.x, p.y -= o .y; return Po(p.x * cos(alpha) - p.y * sin(alpha), p.y * cos(alpha) + p.x * sin(alpha)) + o; } // <<= ' 0. I/O Accelerator interface ., template<class T> inline void RD(T &x){ //cin >> x; scanf("%d", &x); //char c; for (c = getchar(); c < '0'; c = getchar()); x = c - '0'; for (c = getchar(); c >= '0'; c = getchar()) x = x * 10 + c - '0'; //char c; c = getchar(); x = c - '0'; for (c = getchar(); c >= '0'; c = getchar()) x = x * 10 + c - '0'; } const DB no_solution = -1; int ____Case; template<class T> inline void OT(const T &x){ printf("Case #%d: ", ++____Case); printf("%d", x); puts(""); } /* .................................................................................................................................. */ const int N = 50; bool Map[N][N]; bool exist[100 + 5][100 + 5]; int res; int main() { freopen("D-small-practice.in", "r", stdin); freopen("out.txt", "w", stdout); int cases, cur; int h, w, D; int s, px, py, ii, jj, ox, oy, x0, y0; double cx, cy, a, b, d; bool destroyed; Rush{ RD(h, w, D); REP_2(i, j, h, w){ char t; RC(t); if (t == 'X') x0 = i, y0 = j; Map[i][j] = t != '#'; } res = 0; int i, j, k; for (i=x0-1;Map[i][y0];--i); if (((x0-i)<<1)-1<=D) ++res; for (i=x0+1;Map[i][y0];++i); if (((i-x0)<<1)-1<=D) ++res; for (i=y0-1;Map[x0][i];--i); if (((y0-i)<<1)-1<=D) ++res; for (i=y0+1;Map[x0][i];++i); if (((i-y0)<<1)-1<= D) ++res; RST(exist); FOR(ii, -D+1, D) if (ii) FOR(jj, -D+1, D) if (jj && sqr(ii)+sqr(jj)<=sqr(D)){ k = abs(__gcd(ii, jj)), i = ii / k, j = jj / k; if (exist[i + 50][j + 50]) continue; i = ii, j = jj, cx = x0 + 0.5, cy = y0 + 0.5, d = 0, destroyed = false; do{ if (i < 0) a = (cx - (int)(cx - EPS)) / -i; else a = ((int)(cx + 1 + EPS) - cx) / i; if (j < 0) b = (cy - (int)(cy - EPS)) / -j; else b = ((int)(cy + 1 + EPS) - cy) / j; checkMin(a, b); if (d + a > 1) break; d += a, cx += a * i, cy += a * j; px = cx + EPS, py = cy + EPS; if (cx - px < EPS && cy - py < EPS) { if (i < 0) ox = px--; else ox = px-1; if (j < 0) oy = py--; else oy = py-1; if (!Map[px][py]) { destroyed = true; if (!Map[ox][py]) j = -j, destroyed = false; if (!Map[px][oy]) i = -i, destroyed = false; } } else if (cx - px < EPS) { if (i < 0) --px; if (!Map[px][py]) i = -i; } else if (cy - py < EPS) { if (j < 0) --py; if (!Map[px][py]) j = -j; } } while (!destroyed); if (destroyed) continue; a = (x0 + 0.5 - cx) / i, b = (y0 + 0.5 - cy) / j; if (fabs(d + a - 1) < EPS && fabs(d + b - 1) < EPS) { k = abs(__gcd(ii, jj)), i = ii / k, j = jj / k; ++res, exist[i + 50][j + 50] = true; } } OT(res); } }