30 number=VAL(mixture$)

40 IF number>0 THEN PRINT "The string begins with the numbers ";

number

If a string begins with numeric characters, a + or -- sign, VAL converts those

characters to their numeric equivalent. Note that VAL ignores the remainder

of the string following the first non-numeric character it discovers, for example:

PRINT VAL("123g456")

produces 123.

READ, DATA and RESTORE

Many programs need some basic data before they can run, and it is often

convenient to store that data as part of the program. For example, here is a

simple quiz program that includes the questions and answers in DATA

statements:

10 MODE 135

20 PR0Cstart

30 PROCquiz

40 END

50 DEFPROCstart

60 correct=0

70 READ how_many

80 PRINT TAB( 14) "A quiz game"

90 PRINTSTRING$(4,"=")

100 ENDPROC

110 DEFPR0Cquiz

120 FOR question=1 TO how_many

130 READ question$,answer$

140 PRINT'question$

150 INPUT response$

160 IF response$=answer$ THEN PR0Cright ELSE PR0Cwrong

170 NEXT question

180 PRINT '"You had " ;correct;" right out of ";how_many

190 ENDPROC

200 DEFPROCright

210 correct=correct+1

220 IF RND(2) >1 THEN PRINT '"That's right ! " ELSE PRINT '"Well done! "

230 ENDPROC

240 DEFPR0Cwrong

250 PRINT' "No, the answer is:"

260 PRINTanswer$

270 ENDPROC

C 50