PROGRAM Simplex;

CONST
	alpha=1;
	beta=2;
	gamma=0.5;
TYPE
	vektor2=array[1..2] of real;
	vektor3=array[1..3] of real;
	vektor32=array[1..3,1..2] of real;

FUNCTION f(x:real;y:real):real;
BEGIN
     f:=100*sqr(y-x*x)+sqr(1-x);
     {f:=sqr(x)+sqr(y);}
END;

PROCEDURE ZAMEN(VAR x:vektor32; VAR y:vektor3; i1:integer; i2:integer);
VAR
	i:integer;
        c:vektor2;
        d:real;
BEGIN
	FOR i:=1 TO 2 DO
	BEGIN
		c[i]:=x[i1,i];
		x[i1,i]:=x[i2,i];
		x[i2,i]:=c[i];
	END;
        d:=y[i1];
        y[i1]:=y[i2];
        y[i2]:=d;
END;

VAR
	i,j,k:integer;
	x:vektor32;
	y:vektor3;
	c,xt,xc,xe:vektor2;
	yt,ye,yc:real;
	fileout:text;
BEGIN

ASSIGN(fileout,'body.dat');
REWRITE(fileout);

x[1,1]:=0.1;
x[1,2]:=-15.2;
x[2,1]:=4.7;
x[2,2]:=19;
x[3,1]:=14.8;
x[3,2]:=5.9;

y[1]:=f(x[1,1],x[1,2]);
y[2]:=f(x[2,1],x[2,2]);
y[3]:=f(x[3,1],x[3,2]);

FOR k:=1 TO 30 DO
BEGIN

	IF (y[3]<y[2]) THEN ZAMEN(x,y,2,3);
	IF (y[2]<y[1]) THEN
	BEGIN
		ZAMEN(x,y,1,2);
		IF (y[3]<y[2]) THEN ZAMEN(x,y,2,3);
	END;

	WRITELN(fileout,x[1,1]:9:3,x[1,2]:9:3,x[2,1]:9:3,x[2,2]:9:3,x[3,1]:9:3,x[3,2]:9:3,y[1]:9:3);
	WRITELN(y[1]:9:3,' ',y[2]:9:3,' ',y[3]:9:3);
        WRITELN(x[1,1]:9:3,' ',x[1,2]:9:3);
        WRITELN(x[2,1]:9:3,' ',x[2,2]:9:3);
        WRITELN(x[3,1]:9:3,' ',x[3,2]:9:3);
	READLN;

	FOR i:=1 TO 2 DO
	BEGIN
		c[i]:=0;
		FOR j:=1 TO 2 DO c[i]:=c[i]+x[j,i]/2;
	END;

	FOR i:=1 TO 2 DO xt[i]:=c[i]+alpha*(c[i]-x[3,i]);
	yt:=f(xt[1],xt[2]);

	IF (yt<y[3]) THEN
	BEGIN
		FOR i:=1 TO 2 DO x[3,i]:=xt[i];
		y[3]:=yt;
		IF (yt<y[1]) THEN
		BEGIN
			FOR i:=1 TO 2 DO xe[i]:=c[i]+beta*(xt[i]-c[i]);
			ye:=f(xe[1],xe[2]);
			IF (ye<yt) THEN
			BEGIN
				FOR i:=1 TO 2 DO x[3,i]:=xe[i];
				y[3]:=ye;
			END;
		END;
	END;

	IF (yt>y[2]) THEN
	BEGIN
		FOR i:=1 TO 2 DO xc[i]:=c[i]+gamma*(x[3,i]-c[i]);
		yc:=f(xc[1],xc[2]);
		IF (yc<y[3]) THEN
		BEGIN
			FOR i:=1 TO 2 DO x[3,i]:=xc[i];
			y[3]:=yc;
		END
		ELSE BEGIN
			FOR i:=2 TO 3 DO
			FOR j:=1 TO 2 DO x[i,j]:=x[1,j]+gamma*(x[i,j]-x[1,j]);
			y[2]:=f(x[2,1],x[2,2]);
			y[3]:=f(x[3,1],x[3,2]);
		END;
	END;
END;

CLOSE(fileout);

WRITELN('HOTOVO');
READLN;

END.