Let’s continue with the simple Python exercises I’ve been messing around lately. This is a classical question at Dev job interviews, the Fibonacci sequence code. The idea behind this is to come up with code, that sums up the previous 2 member values for a member in the sequence, simply expressed like 1,2,3,5,8,13…

Below are my personal takes on this problem.

**1: The nice and performing solution**

#get fibonacci import sys def main(arg): seq_len = arg seq_len_iterator = 2 var1 = 1 var2 = 2 fibonacci = ([var1, var2]) while seq_len_iterator < seq_len: var3 = var1 + var2 fibonacci.append(var3) i = len(fibonacci) var1 = fibonacci[i-2] var2 = fibonacci[i-1] seq_len_iterator = seq_len_iterator + 1 print(f'Fibonacci sequence for {seq_len} sequence members goes like: {fibonacci}') if __name__ == '__main__': try: arg = int(sys.argv[1]) main(arg) except: print(f'Invalid input, must be integer!')

Execute with the needed sequence member count argument like for instance :

python.exe C:/codility/fibonacci/__main__.py 10

**2: The alternative “nested-iterations” solution** ( Not performing over ~30 sequence members count, durations exponentially grow, however its another example of a valid solution and can be useful if you need to warm oneself during long winter cold nights somewhere outside 🙂 )

#get fibonacci import sys def main(arg): seq_len = arg seq_len_iterator = 2 iterator = 1 var1 = 1 var2 = 2 fibonacci = ([var1, var2]) while seq_len_iterator < seq_len: if iterator == var1 + var2: fibonacci.append(iterator) var1 = var2 var2 = iterator iterator = iterator + 1 seq_len_iterator = seq_len_iterator + 1 #print(f'Fibonacci member found in try #: {iterator}') else: iterator = iterator + 1 print(f'Fibonacci sequence for {seq_len} sequence members goes like: {fibonacci}') if __name__ == '__main__': try: arg = int(sys.argv[1]) main(arg) except: print(f'Invalid input, must be integer!')

Execute with the needed sequence member count argument like for instance :

python.exe C:/codility/fibonacci/__main__.py 10