The program below uses a much more complex function, containing statements
which are explained in the next few sections:
10 MODE 135
20 PR0Cinput_word
30 END
40 DEFPROCinput_word
50 INPUT"Type in a word " ,word$
60 PRINT'"An anagram of that word is ";FNanagram(word$)
70 ENDPROC
80 DEFFNanagram(choice$)
90 length%=LEN(choice$)
100 FOR count=1 TO length%
110 random_letter%=RND( Length%-1 )
120 choice$=RIGHT$(choice$,length%-random_
letter%)+MID$(choice$,random_letter%,1 )+LEFT$(choice$,random_
letter%-1 )
130 NEXT
140 =choice$
Loops
FOR...NEXT
The real power of computers comes from their ability to repeat instructions.
This can transform trivial programs so that they produce very impressive
results.
The FOR...NEXT loop makes the computer repeat a set of instructions a fixed
number of times:
10 MODE 128
20 FOR count=1 TO 100
30 PRINT count
40 NEXT count
Line 20 is the start of the loop, with the variable count being set to 1 initially.
After printing the value of count at line 30, the computer finds the NEXT
statement which indicates the end of the loop.
At this point count is increased by I. Provided that count has not gone beyond
the end value of 100 the computer now repeats all the instructions again.
Line 40 can be written as just:
40 NEXT
C 37