Code Review Assistant

**Code Analysis:** Your function correctly identifies prime numbers, but has efficiency concerns. The nested loop creates O(n²) complexity, which will slow significantly for larger inputs. **Specific Feedback:** The inner loop (line 4) checks all numbers up to `num`, but you only need to check up to √num. Also, checking even numbers after 2 is unnecessary. **Improvement Suggestions:** Implement the Sieve of Eratosthenes for better performance, or at minimum, skip even numbers and limit your range to `int(num**0.5) + 1`.

This prime-finding function works but suffers from significant inefficiency. The nested loop structure results in quadratic time complexity, and you're doing unnecessary work by checking divisibility against all numbers rather than just up to the square root. I'd recommend either implementing a sieve algorithm or, at minimum, adding `if num > 2 and num % 2 == 0: continue` before your inner loop and changing `range(2, num)` to `range(2, int(num**0.5) + 1)`. The logic is sound, but real-world usage would benefit from these optimizations.

**Code Analysis:** The function correctly implements trial division but with O(n²) complexity. **Specific Feedback:** Line 4's inner loop is inefficient—you only need to test divisors up to √num. All even numbers except 2 can be skipped. **Improvement Suggestions:** 1) Add `if num == 2: primes.append(2); continue` and `if num % 2 == 0: continue` after line 3. 2) Change line 4 to `range(3, int(num**0.5) + 1, 2)`. 3) For n > 10000, consider the Sieve of Eratosthenes algorithm.