Find number of trailing zeroes in factorial of a number?

Short answer: public int TrailingZeroes(int n) { int count = 0; while (n > 0) { n /= 5; count += n; } return count; } Explanation: Count factors of 5 in factorial since 2s are plentiful, trailing zeros depend on 5s.

Example code

public int TrailingZeroes(int n) {
int count = 0; while (n > 0) { n /= 5;
count += n;
}
return count;
} Explanation: Count factors of 5 in factorial since 2s are plentiful, trailing zeros depend on 5s.

Real-world example (ShopNest)

In coding rounds, state complexity aloud, write a clear ShopNest-flavored example (orders, carts), then handle edge cases (empty list, null, overflow).

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.