Title: Portal
The meaning of problems: there are n test sample, each sample, enter the four points, the first two points represent a line, two points after two squares represent the diagonal endpoints.
#include <iostream> #include <stdio.h> #include <string.h> #include <algorithm> #include <queue> #include <map> #include <vector> #include <set> #include <string> #include <math.h> #define LL long long #define mem(i, j) memset(i, j, sizeof(i)) #define rep(i, j, k) for(int i = j; i <= k; i++) #define dep(i, j, k) for(int i = k; i >= j; i--) #define pb push_back #define make make_pair #define INF 1e20 #define inf LLONG_MAX #define PI acos(-1) using namespace std; const int N = 1e2 + 5; const double eps = 1e-10; struct Point { double x, y; Point(double x = 0, double y = 0) : x(x), y(y) { } /// 构造函数 }; /// 向量加减乘除 inline Point operator + (const Point& A, const Point& B) { return Point(A.x + B.x, A.y + B.y); } inline Point operator - (const Point& A, const Point& B) { return Point(A.x - B.x, A.y - B.y); } inline Point operator * (const Point& A, const double& p) { return Point(A.x * p, A.y * p); } inline Point operator / (const Point& A, const double& p) { return Point(A.x / p, A.y / p); } inline int dcmp(const double& x) { if(fabs(x) < eps) return 0; else return x < 0 ? -1 : 1; } inline double Cross(const Point& A, const Point& B) { return A.x * B.y - A.y * B.x; } /// 叉积 inline double Dot(const Point& A, const Point& B) { return A.x * B.x + A.y * B.y; } /// 点积 inline double Length(const Point & A) { return sqrt (Dot (A, A));} /// vector length inline Double Angle ( const Point & A, const Point & B) { return ACOS (Dot (A, B) / the Length (A) / the Length (B));} /// vector A, B angle inline Point GetLineIntersection ( const Point P, const Point V, const Point Q, const Point W) { /// the Line and p + v * t Q + w * t of the intersection, the need to ensure that there is an intersection, v and w are direction vectors Point U = P - Q; Double T = Cross (w, U) / Cross (V, w); return P + V * T; } inline BOOL Onsegment (Point p, Point A1, A2 Point) { /// determines whether a point p on the line segment P1P2 return dCMP (Cross (A1 - p, A2 - p)) == 0 && dCMP (Dot (A1 - p , A2 - P)) <= 0 ; } inline BOOL SegmentProperInsection (Point A1, A2 Point, Point B1, B2 Point) { /// determines whether or not the line segment intersects iF (dCMP (Cross (A1 - A2, B1 - B2)) == 0 ) // two parallel line segments return Onsegment (B1, A1, A2) || Onsegment (B2, A1, A2) || Onsegment (A1, B1, B2) || Onsegment (A2, B1, B2); tmp Point = GetLineIntersection (A1, A2 - A1, B1, B2 - B1); return Onsegment(tmp, a1, a2) && Onsegment(tmp, b1, b2); } inline int isPointInpolygon(Point tmp, Point P[], int n) { /// 判断点是否在多边形里 int wn = 0; rep(i, 0, n - 1) { if(Onsegment(tmp, P[i], P[(i + 1) % n])) return -1; /// 边界 int k = dcmp(Cross(P[(i + 1) % n] - P[i], tmp - P[i])); int d1 = dcmp(P[i].y - tmp.y); int d2 = dcmp(P[(i +1) % n].y - tmp.y); if(k > 0 && d1 <= 0 && d2 > 0) wn++; if(k < 0 && d2 <= 0 && d1 > 0) wn--; } if(wn) return 1; /// 外部 return 0; /// 内部 } Point P[N]; void solve() { Point st, ed; double x1, x2, y1, y2; scanf("%lf %lf %lf %lf", & St.x, & st.y, & ed.x, & ed.y); Scanf ( " % LF LF%%% LF LF " , & X1, Y1 &, & X2, & Y2); IF (X1> X2) the swap ( X1, X2); IF (Y1> Y2) the swap (Y1, Y2); P [ 0 ] = Point (X1, Y1); P [ . 1 ] = Point (X1, Y2); P [ 2 ] = Point (X2 , Y2); P [ . 3 ] = Point (X2, Y1); REP (I, 0 , 2 ) { /// sides of the polygon is determined whether the line segment and intersecting iF (SegmentProperInsection (ST, ED, P [I], P [I +. 1 ]) == . 1 ) { the puts ( " T " ); return ; } } IF (isPointInpolygon (ST, P, . 4 ) || isPointInpolygon (ED, P, . 4 )) { /// determines whether there is a line segment endpoint on the border or inside the polygon the puts ( " T " ); return ; } the puts ( " F. " ); } int main () { int _; Scanf ( " % D " , & _); the while (_-- ) Solve ( ); return 0; }