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Pointers: Beyond the Basics 419

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Figure 15.9 illustrates the procedure for adding a new element to an empty list, and

Figure 15.10 illustrates adding a new first element to an existing list.

It’s important to switch the pointers in the correct order. If you reassign the

Caution head pointer first, you will lose the list!

FIGURE15.9

Adding a new element

to an empty linked list.

FIGURE15.10

Adding a new first ele-

ment to an existing list.

new data

NULL

head

NULL

Before addition

new data

NULL

head

After addition

data

next pointer

data

next pointer

new data

NULL

new data

next pointer

data

NULL

head

Before addition

data

next pointer

data

next pointer

data

NULL

head

After addition

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