Cf -- 1c

1 // accepted 0 kb 60 MS 2 // given the three points on the positive multi deformation, the minimum area of the positive multi-shape 3 // remember the distance between the three points A, B, c; 4 // cosa 5 obtained by cosine theorem // to obtain the center angle of Sina, R 6, radius of the outer circle of the positive polygon, and set the three edges to theta1, theta2, theta3 7 // The center angle of the regular polygon is gcd (theta1, gcd (theta2, theta3) 8 // Where gcd (theta1, theta2) so far, we can find the area of the positive polygon 10 # include <cstdio> 11 # include <cstring> 12 according to the radius R and center angle of the outer circle of the positive polygon. # include <iostream> 13 # include <queue> 14 # include <cmath> 15 # include <algorithm> 16 Using namespace STD; 17 const double Pi = ACOs (-1.0 ); 18/** 19 * This is a documentation comment block20 * @ authr songt21 */22 struct point23 {24 Double X, Y; 25} p [3]; 26 double getdis (point P1, point P2) 27 {28 return SQRT (p1.x-p2.x) * (p1.x-p2.x) + (p1.y-p2.y) * (p1.y-p2.y); 29} 30 double gcd (double A, double B) 31 {32 If (FABS (B) <1e-4) return; 33 If (FABS (a) <1e-4) return B; 34 return gcd (B, fmod (A, B); 35} 36 V Oid slove () 37 {38 double A = getdis (P [1], p [2]); 39 Double B = getdis (P [1], p [3]); 40 double C = getdis (P [2], p [3]); 41 double cosa = (B * B + C * C-A *) /(2 * B * C); 42 double Sina = SQRT (1-cosa * COSA); 43 Double R = A/(2 * Sina ); 44 // printf ("r = % lf \ n", R); 45 double thetaa = 2 * asin (A/(2 * r )); 46 Double thetab = 2 * asin (B/2/R); 47 // double thetac = 2 * asin (C/2/R ); 48 double thetac = 2 * pi-thetaa-thetab; 49 // printf ("% lf \ n", thetaa + thetab + thetac); 50 Double Theta = gcd (thetaa, gcd (thetab, thetac); 51 // printf ("Theta = % lf \ n", theta ); 52 // printf ("Pi = % lf \ n", Pi); 53 double S = 2 * PI/Theta * r/2 * sin (theta ); 54 printf ("%. 6lf \ n ", S); 55} 56 int main () 57 {58 While (scanf (" % lf ", & P [1]. x, & P [1]. y, & P [2]. x, & P [2]. y, & P [3]. x, & P [3]. Y )! = EOF) 59 slove (); 60 return 0; 61}

View code

 

Cf -- 1c