I found this source on my attic.
Writing this about 20 years ago.
And published to the C64-Mag.
I remember I got 50 DM (25 Euro) for this...
...good old days...

10 REM BOULDER DASH
20 :
30 POKE53280,0:POKE53281,0:PRINT"hp"
40 :REM INIT
50 PRINT"sqqq"
60 PRINT,"----------------"
70 PRINT,"- BOULDER DASH -"
80 PRINT,"----------------"
90 PRINT"qqq"
100 PRINT"---------------------"
110 PRINT"- SPIELER 0..9 ? -"
120 PRINT"---------------------"
130 PRINT"qq"
135 PRINT"---------------------"
140 PRINT"- ZEIT 0..1 ? -"
145 PRINT"---------------------"
150 PRINT"uuuuuuuuue"
155 PRINT,"jjjjjjj";:POKE204,0
160 GETA$:IFA$<"0"ORA$>"9"THEN160
165 PRINTA$;" "
170 PRINT"qqqq"
175 PRINT,"jjjjjjj";:POKE204,0
180 GETB$:IFB$<"0"ORB$>"1"THEN180
185 PRINTB$;" ":POKE204,1
190 :
200 IFA$="0"THENPOKE34670,169:GOTO220
210 POKE34646,VAL(A$):POKE34752,VAL(A$)
220 IFB$="0"THENPOKE28896,234:POKE28897,234:POKE28898,234
230 SYS35507:END

This patched BoulderDash I to have unlimited lives
or 1..9 lives and/or to switch off the time limit.

HerzAusGold