Rosetta Code

Leap year

Determine whether a given year is a leap year using the Gregorian calendar rules.

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Sourcerosettacode/popular/leap_year.vibe
def leap_year?(year: int) -> bool
  if year % 400 == 0
    return true
  elsif year % 100 == 0
    return false
  elsif year % 4 == 0
    return true
  end
  false
end

def run -> array<{ leap: bool, year: int }>
  years = [1900, 2000, 1996, 1997, 2024, 2025, 2100, 2400]
  results: array<{ leap: bool, year: int }> = []
  i = 0
  while i < years.length
    results.push({ year: years.fetch(i), leap: leap_year?(years.fetch(i)) })
    i = i + 1
  end
  results
end

Output

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