Rosetta Code

Happy numbers

Classify happy numbers by iterating the sum-of-squares process and list the first twelve.

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Sourcerosettacode/popular/happy_numbers.vibe
def digit_square_sum(value: int) -> int
  current = value
  total = 0

  while current > 0
    digit = current % 10
    total = total + (digit * digit)
    current = current // 10
  end

  total
end

def happy?(value: int) -> bool
  current = value

  while current != 1 && current != 4
    current = digit_square_sum(current)
  end

  current == 1
end

def first_happy_numbers(count: int) -> array<int>
  values: array<int> = []
  candidate = 1

  while values.length < count
    if happy?(candidate)
      values.push(candidate)
    end
    candidate = candidate + 1
  end

  values
end

def run -> { first_five: array<int>, nineteen: bool, twenty: bool }
  {
    first_five: first_happy_numbers(5),
    nineteen: happy?(19),
    twenty: happy?(20)
  }
end

Output

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