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Arrays of Pointers

We can have arrays of pointers since pointers are variables.

Example use:

Sort lines of text of different length.

NOTE: Text can't be moved or compared in a single operation.

Arrays of Pointers are a data representation that will cope efficiently and conveniently with variable length text lines.

How can we do this?:

• Store lines end-to-end in one big char array (see figure). \n will delimit lines.
• Store pointers in a different array where each pointer points to 1st char of each new line.
• Compare two lines using strcmp() standard library function.
• If 2 lines are out of order - swap pointer in pointer array (not text).

Arrays of Pointers (String Sorting Example)

This eliminates:

• complicated storage management.
• high overheads of moving lines.