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reverse_lines

Language/Type: PHP recursion streams file input

Write a recursive function named reverse_lines that accepts a file name $filename as its parameter and prints the lines of that file in reverse order. For example, if an input file named poem.txt contains the following text: 

Roses are red,
Violets are blue.
All my base
Are belong to you.

Then the call of reverse_lines("poem.txt"); should produce the following console output: 

Are belong to you.
All my base
Violets are blue.
Roses are red,

You may assume that the input file exists and is readable.

Constraints:

  • Your function must be recursive and must not use loops.
  • Your solution must not change the contents of the file data.
  • Your solution should read the file only once, not make multiple passes over the file data. You may find a helper function helpful for meeting this requirement, passing in an array of lines from the read file argument to a helper function which implements the recursive behavior.
Function: Write a PHP function as described, not a complete program.

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