100 ' BUBBLE SORT DEMO FOR MODEL I/III
105 DEFINT A-Z
110 CLS: P= 0
120 FOR I = 15360 TO 15615   'FIRST 255 SCREEN BLOCKS
130    A = RND(127):IF A < 32 THEN GOTO 130
135   IF A < 32 THEN GOTO 130   ' PREVENTS CONTROL CHARACTERS
140    POKE I,A                 'PUTS CHARACTER ON SCREEN
150 NEXT I
160 S=0                          'RESETS SWAP FLAG
170    FOR I = 15360 TO 15614
180       A = PEEK(I): B = PEEK(I+1): IF A<= B THEN GOTO 200
190       S = S+1 : POKE I,B:POKE I+1, A   'EXCHANGE
200    NEXT I
210    P=P+1:PRINT @530,"#SWAPS =";S;"PASS= ";P
220 IF S <> 0 THEN GOTO 160 ELSE GOTO 220
