1000 screen 12:cls
1001 print"‚€™…ˆ…"
?"เฅฎกเ งฎข ญจฅ ชฎฎเคจญ โ"
?:PRINT" X=X1*COS(F)-Y1*SIN(F)":PRINT" Y=X1*SIN(F)+Y1*COS(F)"

1002 PRINT:PRINT" ƒ„… X1,Y1-ŠŽŽ„ˆ€’› ‚ Ž‚…“’Ž‰ ‘ˆ‘’…Œ…, € X,Y- ‚ …Ž„‚ˆ†Ž‰":a$="<Esc>- ‚๋ๅฎค"
1003 locate 17,34:print a$
1010 xc=320:yc=270
1012 ky=(800/(3*640))*(480/200)
1020 a=200
1030 f=0
1040 df=.06
1050 dim a(4),b(4),x(4),y(4),ox(4),oy(4)
1060 a(1)=-a/2:b(1)=a(1):a(2)=a(1):b(2)=-b(1):a(3)=-a(1):b(3)=b(2)
1070 a(4)=a(3):b(4)=b(1)
1072 for i=1 to 4
1073 ox(i)=cos(f)*a(i)-sin(f)*b(i)+xc:oy(i)=a(i)*sin(f)+b(i)*cos(f):oy(i)=ky*oy(i)+yc
1074 next i
1080 sf=sin(f):cf=cos(f)
1100 for i=1 to 4
1110 x(i)=cf*a(i)-sf*b(i)+xc
1120 y(i)=a(i)*sf+b(i)*cf:y(i)=ky*y(i)+yc
1130 next i
1132 m=0:gosub 2000
1134 for i=1 to 4:ox(i)=x(i):oy(i)=y(i):next i
1136 m=9:gosub 2000:delay .04
1170 f=f+df
1175 IF INKEY$=chr$(27) THEN STOP
1177 if abs(f)>2 then df=-df:sound 1000,.1
1190 goto 1080
2000 for i=1 to 3:line(ox(i+1),oy(i+1))-(ox(i),oy(i)),m:next i
2010 line(ox(4),oy(4))-(ox(1),oy(1)),m:return