| 1 | 1 | def prime(number): |
| 2 | pass | |
| 2 | # Edge Case: Input is less than 1 | |
| 3 | if number < 1: | |
| 4 | raise ValueError('there is no zeroth prime') | |
| 5 | ||
| 6 | # Edge Case: First prime number | |
| 7 | if number == 1: | |
| 8 | return 2 | |
| 9 | ||
| 10 | primes = [2] | |
| 11 | candidate = 3 | |
| 12 | ||
| 13 | # Edge Case: Large prime numbers | |
| 14 | while len(primes) < number: | |
| 15 | is_prime = True | |
| 16 | # Check if candidate is divisible by any previously found prime | |
| 17 | for p in primes: | |
| 18 | # Edge Case: Optimize by only checking up to square root of candidate | |
| 19 | if p * p > candidate: | |
| 20 | break | |
| 21 | if candidate % p == 0: | |
| 22 | is_prime = False | |
| 23 | break | |
| 24 | ||
| 25 | if is_prime: | |
| 26 | primes.append(candidate) | |
| 27 | ||
| 28 | # Move to next odd number (since even numbers > 2 are not prime) | |
| 29 | candidate += 2 | |
| 30 | ||
| 31 | return primes[number - 1] | |
| 32 | ||
| 33 | # Handled Edge Cases: Input is less than 1, First prime number, Large prime numbers, Optimize by only checking up to square root of candidate |