OpenStudy (anonymous):

solutions to problem set 1.... please just post solution... been trying for a few days now

6 years ago
OpenStudy (anonymous):

both problems

6 years ago
OpenStudy (anonymous):

Here is what i finally managed to get a hold of for part 1: def primes(n): """ returns a list of prime numbers from 2 to n """ if n < 2: return [] if n == 2: return [2] # create a list of odd numbers from 3 to n nums = list(range(3, n+1, 2)) nums_len = (n // 2) - 1 + (n % 2) idx = 0 idx_sqrtn = (int(n**0.5) - 3) // 2 while idx <= idx_sqrtn: nums_idx = (idx << 1) + 3 for j in range(idx*(nums_idx+3)+3, nums_len, nums_idx): # if not a prime replace with zero nums[j] = 0 idx += 1 while idx <= idx_sqrtn: if nums[idx] != 0: break idx += 1 # remove all the zero entries return [2] + [x for x in nums if x != 0] print('-' * 50) # print 50 dashes, cosmetic num = 7919 primeList = primes(num) print("List of prime numbers from 2 to %d:" % num) print(primeList)

6 years ago