Commodore PET - Page 235

[68][Ej
x ŒBJ l]g
IP1$1}
+em:J
+1 P3$1}
+1 P4$!
To add P3$ and P4$ together. the values of P3$ and P4$ are passed to the
parameters A$ and
B$ before calling the addition subroutine 2000:
1132 A$=P3$:B$=P4$:GOSUB 2000
A$ 1919191810101010)01010101
B$ 191919181010101110101010101010101
The addition subroutine adds the corresponding digits of P3$ and P4$. truncates
any leading
zeros. and returns sum C$ to the main program. where C$ is con-
verted to M2$:
1135 M2$=C$
At this point. M1$ is the sum of P1$ and P2$. and M2$ is the sum of P3$
and P4$. To get the sum of ail four products. M1$ and M2$ must be added
together:
+~
1 c$1
The addition subroutine is called a third time to add M 1$ and M2$ together
to get the final answer.
C$.
1140 A$=Ml$:B$=M2$
A$ 1919191819191919)01010/11
B$ 191919181919191910101011101010101
1150 OOSUB 2000
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