Encore 
 1def factorial(n):
 2    """
 3    Calculate the factorial of a non-negative integer.
 4    """
 5    if n == 0:
 6        return 1
 7    else:
 8        return n * factorial(n-1)
 9
10# Example usage:
11# print(factorial(5))

This Python function factorial(n) calculates the factorial of a given non-negative integer n recursively.

  • Base Case: If n is 0, it returns 1 (since 0! = 1).
  • Recursive Step: If n is greater than 0, it returns n multiplied by the factorial of n-1.

The example usage shows how to call the function with factorial(5), which would return 120.

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JavaScript: debounce helper

 1const debounce = (fn, wait) => {
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 3  return (...args) => {
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 6  };
 7};
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 1function greet(string $name, string $punct = !) {
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Test-Driven Development

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