Add 1 only to Integers in an array in ruby

Question

I have an array which contains mixed classes:

arr = ["I", "have", 2, "dimes", "and" , 3, "nickels"]

How do I perform addition on the integers in the array without modifying the strings?

The expected output is,

["I", "have", 3, "dimes", "and" , 4, "nickels"]

Answer 1

def add_to_integers(ary, n)
  ary.map { |i| i.is_a?(Integer) ? (i + n) : i }
end

add_to_integers([1, 'foo'], 1)
# => [2, "foo"]