happy_number.rb

# @param {Integer} n
# @return {Boolean}
def is_happy(n)
    iterated = []
    found = false
    loop do
        found = iterated.include? n
        iterated << n
        nxt = 0
        while n>0 do
            digit = n % 10
            nxt +=  digit * digit
            n = (n / 10).floor
        end
        n = nxt
        break if n==1 || found
    end
    n==1
end