--description--

For any $N$, let $f(N)$ be the last five digits before the trailing zeroes in $N!$.

For example,

$$\begin{align} & 9! = 362880 \; \text{so} \; f(9) = 36288 \\ & 10! = 3628800 \; \text{so} \; f(10) = 36288 \\ & 20! = 2432902008176640000 \; \text{so} \; f(20) = 17664 \end{align}$$

Find $f(1,000,000,000,000)$

--hints--

factorialTrailingDigits() should return 16576.

assert.strictEqual(factorialTrailingDigits(), 16576);

--seed--

--seed-contents--

function factorialTrailingDigits() {

  return true;
}

factorialTrailingDigits();

--solutions--

// solution required