input: Write a function to calculate compound interest based on given investment amount, rate of interest, and time period. Ensure the function returns the calculated compound interest value. If the input values are invalid (e.g., negative values), return a specific error message or handle it as per the requirements.
  def compoundInterest(investment_amount, rate_of_interest, time):
      if investment_amount < 0 or rate_of_interest < 0 or time < 0:
          return "Invalid input values"
      compound_interest = investment_amount * (pow((1 + rate_of_interest / 100), time))
      return compound_interest
  
  assert compoundInterest(1000, 5, 5) == 1276.2815625000003
  assert compoundInterest(2000, 3, 10) == 2687.8326700110167
  assert compoundInterest(1500, 7, 4) == 1967.1513572899994
  assert compoundInterest(-1000, 5, 5) == "Invalid input values"
  assert compoundInterest(1000, -5, 5) == "Invalid input values"
  assert compoundInterest(1000, 5, -5) == "Invalid input values"
output: def compoundInterest(investment_amount, rate_of_interest, time):
      if investment_amount < 0 or rate_of_interest < 0 or time < 0:
          return "Invalid input values"
      compound_interest = investment_amount * (pow((1 + rate_of_interest / 100), time))
      return compound_interest