Лови такой вариант: 
| Код | Program Triangles;
uses crt, graph;
const MaxPoints = 100;
const delta = 0.01;
type
TPoint = PointType;
TPointArray = array [1..MaxPoints] of TPoint;
TMinimumInfo = record
P1 : TPoint;
P2 : TPoint;
P3 : TPoint;
Square : double;
end;
var
gd,gm :integer;
NumPts :integer;
i :integer;
j,k :integer;
sleep :longint;
Points :TPointArray;
Min :TMinimumInfo;
procedure CheckTriangleInfo(P1,P2,P3:TPoint;var MinimumInfo:TMinimumInfo);
var
S:double;
p:double;
a,b,c:double;
begin
a:=sqrt(sqr(1.0*(P2.X-P1.X))+sqr(1.0*(P2.Y-P1.Y)));
b:=sqrt(sqr(1.0*(P3.X-P2.X))+sqr(1.0*(P3.Y-P2.Y)));
c:=sqrt(sqr(1.0*(P1.X-P3.X))+sqr(1.0*(P1.Y-P3.Y)));
p:=(a+b+c)/2;
S:=sqrt(p*(p-a)*(p-b)*(p-c));
if (S<MinimumInfo.Square)or(MinimumInfo.Square<0) then
begin
MinimumInfo.P1:=P1;
MinimumInfo.P2:=P2;
MinimumInfo.P3:=P3;
MinimumInfo.Square:=S;
end;
end;
function TriangleIsCorrect(P1,P2,P3:TPoint):boolean;
var
a,b,c:double;
begin
TriangleIsCorrect:=true;
a:=sqrt(sqr(1.0*(P2.X-P1.X))+sqr(1.0*(P2.Y-P1.Y)));
b:=sqrt(sqr(1.0*(P3.X-P2.X))+sqr(1.0*(P3.Y-P2.Y)));
c:=sqrt(sqr(1.0*(P1.X-P3.X))+sqr(1.0*(P1.Y-P3.Y)));
if (abs(a - (b+c))<delta)or
(abs(b - (a+c))<delta)or
(abs(c - (a+b))<delta) then TriangleIsCorrect:=false;
end;
Procedure DrawAllPoints;
var
Cur:integer;
begin
SetColor(white);
for Cur:=1 to NumPts do
begin
Circle(Points[Cur].X,Points[Cur].Y,2);
FloodFill(Points[Cur].X,Points[Cur].Y,white);
end;
end;
procedure DrawTriangle(P1,P2,P3:TPoint;Filled:boolean);
var
Pts:array [1..4] of TPoint;
begin
Pts[1]:=P1;
Pts[2]:=P2;
Pts[3]:=P3;
Pts[4]:=P1;
SetColor(Random(10)+3);
if not Filled then DrawPoly(4,Pts) else FillPoly(4,Pts);
end;
begin
NumPts:=0;
Min.Square:=-1.0;
while (NumPts<=2)or(NumPts>MaxPoints) do
begin
clrscr;
Write('Введите количество точек: ');
Readln(NumPts);
end;
for i:=1 to NumPts do
begin
Write('Точка ',i,'. Координата Х (0..640):');
Readln(Points[i].X);
if (Points[i].X<10) then Points[i].X:=10;
if (Points[i].X>630) then Points[i].X:=630;
Write('Точка ',i,'. Координата Y (0..480):');
Readln(Points[i].Y);
if (Points[i].Y<10) then Points[i].Y:=10;
if (Points[i].Y>470) then Points[i].Y:=470;
end;
InitGraph(gd,gm,'');
ClearDevice;
If GraphResult <> grOk Then
begin
Writeln('Не удалось инициализировать графический режим...');
Writeln('Завершение работы');
Halt(1);
end;
for i:=1 to NumPts-2 do
for j:=i+1 to NumPts-1 do
for k:=j+1 to NumPts do
begin
if not TriangleIsCorrect(Points[i],Points[j],Points[k]) then continue;
ClearDevice;
DrawAllPoints;
CheckTriangleInfo(Points[i],Points[j],Points[k],Min);
DrawTriangle(Points[i],Points[j],Points[k],false);
for sleep:=1 to 100000000 do ;
end;
ClearDevice;
DrawAllPoints;
DrawTriangle(Min.P1,Min.P2,Min.P3,true);
while keypressed do readkey;
readkey;
CloseGraph;
end. |
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