$0)$ Write a simple loop that, for each record r in the list L$,$ changes r$.$dat to be r$.$dat plus all of the $.$dat

values in the records that precede r in the $($original$)$ list L$.$

So if the numbers in the list are $3,4,5,6,7,$ then they are changed to $3,7,12,18,25.$

Solution:

sum $0$; $\{$ So sum is a local identifier $\}$

$`$ L; $\{$ where L was defined earlier. The assignment to $`$ keeps L pointing at the front of the list $\}$

while $`6=$ Nil do $\{$ You might prefer null $\}$

sum $$ sum $+`.$dat

$`.$dat $$ sum;

$``.$next

endwhile;

$1\mathrm{.}1)$ Write a simple sequence of instructions that processes two singly linked lists Y and M by removing the

first record in Y $($if Y $6=$ Nil$)$ and prepending that record at the front of list M so that M now has this

new element as the first record followed by the old M$,$ and Y no longer contains what had been its first

record. In other words, you have a list Y $,$ and I have a list M$.$ Present instructions that pull off your head,

and place it on top of mine.

$1\mathrm{.}2)$ Write a simple loop that reverses the list Y $,$ and gives this new list the name Y $.$

Does part i make this easier?

$1\mathrm{.}3)$ Give a simple, high$-$level three line description $($do this, do that, do this$)$ of an iterative method to modify

L so that for each record r in the list, r$.$dat is changed to be r$.$dat plus all of the $.$dat values in the

records that follow $($succeed$)$ r in the $($original$)$ list L$.$

So if the numbers in the list are $3,4,5,6,7,$ then they are changed to $25,22,18,13,7.$

Detailed pseudocode is unnecessary for this part. Does part ii make this easier? $($Your answer could be

no$.)$

$1\mathrm{.}4)$ Find a simple, two$-$pass iterative solution $($i$.$e$.,$ which processes all of L twice$)$ to modify L to have the

sums as requested in $1\mathrm{.}3,$ but without ever changing any of its pointers. You can present the pseudocode,

or explain your answer at a higher level.