7 kyu - Switcheroo.md

Task

My solution

def switcheroo(x) 
  x.tr("ab", "ba")
end

Explanation

1. .tr replaces the strings a and b with their opposite b and a. You can also use gsub! in this situation but tr is easier for this one

Use tr when you want to replace (translate) single characters.

tr matches on single characters (not via a regular expression), therefore the characters don't need to occur in the same order in the first string argument. When a character is found, it is replaced with the character that is found at the same index in the second string argument:

'abcde'.tr('bda', '123') #=> "31c2e"

'abcde'.tr('bcd', '123') #=> "a123e" Use gsub when you need to use a regular expression or when you want to replace longer substrings:

'abcde'.gsub(/bda/, '123') #=> "abcde"

'abcde'.gsub(/b.d/, '123') #=> "a123e"