' Programmed by John Paul Pruess.
' Completed on July 18th, 1997.
'
' Some source taken from Harper & Row
' Geometry by Max A. Sobel, pub. Scribner
' Laidlaw, NY.

10 CLS
20 INPUT "Measure of Angle A"; A
30 IF A <= 0 THEN 10
40 IF A >= 180 THEN 10
50 INPUT "Measure of Angle B"; B
60 IF B <= 0 THEN 50
70 IF B >= 180 THEN 50
80 LET E = (A + B)
90 PRINT "Exterior angle = "; E
100 INPUT "Another (Y/N)"; YN$
110 IF YN$ = "Y" THEN GOTO 10
120 IF YN$ = "y" THEN GOTO 10
130 IF YN$ = "N" THEN GOTO 150
140 IF YN$ = "n" THEN GOTO 150 ELSE BEEP: GOTO 100
150 END