Ruby Quizzes

Solutions?

If you find a better solution (or equally good), please open an issue with the question id, e.g.: RQS-001.

Add a Quiz?

Please do so. And please add the quiz in this form: RQS-xxx where xxx is a 3-digit integer.

RQS-001

# Input:
#
# str_perm_char("yes")
#
# Output:
#
# ["yes", "yeS", "yEs", "yES", "Yes", "YeS", "YEs", "YES"]

RQS-002

# Input:
#
# str_perm("abc")
#
# Output
#
# ["abc", "acb", "bac", "bca", "cab", "cba"]

RQS-003

# Input
#
# truth_table(bits: 3)
#
# Output
#
# [[0, 0, 0],
#  [0, 0, 1],
#  [0, 1, 0],
#  [0, 1, 1],
#  [1, 0, 0],
#  [1, 0, 1],
#  [1, 1, 0],
#  [1, 1, 1]]

RQS-004

source: http://ruby-china.org/topics/1504

Implement a rand_split method, modify an array into array which composed of elements, and every element's size is <= max_element elements.

rand_split(array, max_element)
pry> p rand_split (0..10).to_a, 3
pry> [[0], [1,2], [3, 4, 5], [6, 7], [8], [9, 10]]

BONUS: add unit test or minitest.

RQS-005

source: http://ruby-china.org/topics/1517

Given two parameters:

• targeting integer, e.g. 5
• an array with numbers, e.g. [-1, 0, 1, 2, 3, 4]

Objective:

Use the numbers in array (only used once) in which their sum is equal to targeting integer (+). Return an array which satisfy this constraint.

E.g.:

targeting integer: 5

Given array: [-1, 0, 1, 2, 3, 4]

Output will be:

[1, 4], [2, 3], [-1, 2, 4], [0, 1, 4], [0, 2, 3], [-1, 0, 2, 4], [-1, 1, 2, 3]