The Trailing Zeros

Counting the Void

Trailing zeros in a factorial are caused by pairs of 2 and 5. Since factorials always have more 2s than 5s, we only need to count how many factors of 5 exist between 1 and $N$.

The Assignment

Your function receives a parameter num.

1. Initialize count to 0.
2. Use a while loop that continues as long as num / 5 is at least 1.
3. In each step:
   • Divide num by 5 and round down (Math.floor).
   • Add this result to your count.
4. After the loop, print the final count.