Ruby Array : Modification

By - 
chars = ["a", "b", "c"]
=> ["a", "b", "c"]

Insertion

chars.insert( 1, "d" )
=> ["a", "d", "b", "c"]

Modify one element

chars = ["a", "b", "c"]
chars[1] = "d"
=> "d"

chars
=> ["a", "d", "b"]

Modify multiple elements using range

chars = ["a", "b", "c"]
=> ["a", "b", "c"]

chars[1..2] = "d", "e"
=> ["d", "e"]

chars
=> ["a", "d", "e"]

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