Is the Input Factorial of an Integer?

Published by sabonchi in
loopsmathrecursionvalidation

Create a function that checks if a given integer is exactly the factorial of an integer or not. true if it is, false otherwise.

Examples

isFactorial(2) ➞ true
// 2 = 2 * 1 = 2!

isFactorial(27) ➞ false

isFactorial(24) ➞ true
// 24 = 4 * 3 * 2 * 1 = 4!

Notes

  • No error handling is necessary. Inputs are all positive integers.
  • Alternatively, you can solve this with a recursive approach.
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