ответ:
uses graphabc;
var xx,yy,u: integer;
procedure growl(x,y,r: integer);
var i: byte;
begin
for i: =1 to r do
begin
circle(x,y,i);
sleep(5);
end;
end;
procedure growr(x,y: integer);
var i: byte;
begin
for i: =1 to 20 do
begin
ellipse(x-5,y-(i),x-(i*3),y+(i));
ellipse(x+5,y-(i),x+(i*3),y+(i));
ellipse(x-(i),y-5,x+(i),y-(i*3));
ellipse(x-(i),y+5,x+(i),y+(i*3));
sleep(3);
end;
end;
procedure fall;
var r,prer,i: byte;
x,y: integer;
begin
for i: =1 to 10 do
begin
x: =random(160)-80+windowwidth div 2;
prer: =0;
r: =random(10)+10;
for y: =80+windowheight div 2 to windowheight+30 do
begin
setpencolor(clwhite);
circle(x,y-1,prer);
setpencolor(clblack);
circle(x,y,r);
prer: =r;
sleep(3);
end;
end;
end;
procedure growd (x,y: integer);
var i: byte;
begin
for i: =20 downto 5 do
begin
clearwindow;
setbrushcolor(clgreen);
ellipse(x-5,y-(20),x-(60),y+(20));
ellipse(x+5,y-(20),x+(60),y+(20));
ellipse(x-(20),y-5,x+(20),y-(60));
ellipse(x-(20),y+5,x+(20),y+(60));
setbrushcolor(rgb(255,255-((20-i)*10),255-((20-i)*;
circle(x-i,y-i,i);
circle(x+i,y-i,i);
circle(x+i,y+i,i);
circle(x-i,y+i,i);
sleep(5);
end;
end;
var j: integer;
begin
repeat
setbrushcolor(clgreen);
growr(windowwidth div 2,windowheight div 2);
setbrushcolor(clwhite);
for j: =1 to 360 do
if j mod 10=0 then
begin
xx: =round(windowwidth div 2+20*cos(pi*(u+(j*10))/180));
yy: =round(windowheight div 2+20*sin(pi*(u+(j*10))/180));
growl(xx,-j) div 10));
end;
sleep(100);
fall;
growd (windowwidth div 2,windowheight div 2);
sleep(100);
until false;
end.
объяснение:
using System;
class Program
{
static void Main()
{
int x1 = 2, y1 = 1;
int x2 = 6, y2 = 5;
int x3 = 10, y3 = 1;
var a = Distance(x2, y2, x3, y3);
var b = Distance(x1, y1, x3, y3);
var c = Distance(x2, y2, x1, y1);
Console.WriteLine("S = {0}", Square(a, b, c));
Console.ReadKey();
}
//растояние между точками
static double Distance(int x1, int y1, int x2, int y2)
{
return Math.Sqrt((x2 - x1) * (x2 - x1) + (y2 - y1) * (y2 - y1));
}
//формула герона
static double Square(double a, double b, double c)
{
var p = (a + b + c) / 2;
return Math.Sqrt(p * (p - a) * (p - b) * (p - c));
}
// теорема косинусов
static double Angle(double a, double b, double c)
{
return Math.Acos((b * b + c * c - a * a) / (2 * b * c));
}
static bool IsAcuteAngel(double alpha)
{
return alpha < Math.PI / 2;
}
}