CLS
100 INPUT "enter L to convert to LOG. D to convert to decimal"; A$
IF A$ = "L" THEN
   INPUT "ENTER DECIMAL"; D
   L = LOG(D) / LOG(10)
   PRINT "LOG OF "; D; " IS "; L
   PRINT "  "
   END IF
IF A$ = "D" THEN
   INPUT "ENTER LOG"; L
   D = 10 ^ L
   PRINT "INVERSE LOG OF "; L; " IS "; D
   PRINT "   "
   END IF
GOTO 100