Task 1: Binary String

You are given an integer, $n > 0.
Write a script to find all possible binary numbers of size $n bits.

Example 1

Input: $n = 2
Output: 00, 11, 01, 10

Example 2

Input: $n = 3
Output: 000, 001, 010, 100, 111, 110, 101, 011

MY NOTES: very easy

GUEST LANGUAGE: As a bonus, I also had a go at translating ch-1.pl
into C (look in the C directory for the translation)


Task 2: Odd String

You are given a list of strings of same length, @s.

Write a script to find the odd string in the given list. Use positional
value of alphabet starting with 0, i.e. a = 0, b = 1, ... z = 25.

Find the difference array for each string as shown in the example. Then
pick the odd one out.

Example 1:

Input: @s = ("adc", "wzy", "abc")
Output: "abc"

Difference array for "adc" => [ d - a, c - d ]
                           => [ 3 - 0, 2 - 3 ]
                           => [ 3, -1 ]

Difference array for "wzy" => [ z - w, y - z ]
                           => [ 25 - 22, 24 - 25 ]
                           => [ 3, -1 ]

Difference array for "abc" => [ b - a, c - b ]
                           => [ 1 - 0, 2 - 1 ]
                           => [ 1, 1 ]

The difference array for "abc" is the odd one.

Example 2:

Input: @s = ("aaa", "bob", "ccc", "ddd")
Output: "bob"

Difference array for "aaa" => [ a - a, a - a ]
                           => [ 0 - 0, 0 - 0 ]
                           => [ 0, 0 ]

Difference array for "bob" => [ o - b, b - o ]
                           => [ 14 - 1, 1 - 14 ]
                           => [ 13, -13 ]

Difference array for "ccc" => [ c - c, c - c ]
                           => [ 2 - 2, 2 - 2 ]
                           => [ 0, 0 ]

Difference array for "ddd" => [ d - d, d - d ]
                           => [ 3 - 3, 3 - 3 ]
                           => [ 0, 0 ]

The difference array for "bob" is the odd one.

MY NOTES: Hmm..  not always a single odd one out.  What are we supposed
to do if there is no odd one out?