Python/dynamic_programming/fibonacci.py

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2016-09-26 10:28:43 +00:00
"""
This is a pure Python implementation of Dynamic Programming solution to the fibonacci sequence problem.
"""
class Fibonacci:
def __init__(self, N=None):
if N:
self.fib_array = [0] * (N + 1)
self.fib_array[0] = 0
self.fib_array[1] = 1
for i in range(2, N + 1):
self.fib_array[i] = self.fib_array[
i - 1] + self.fib_array[i - 2]
else:
self.fib_array = [None] * (N + 1)
def get(self, sequence_no=None):
if sequence_no:
if sequence_no < len(self.fib_array):
return print(self.fib_array[:sequence_no])
else:
print("Out of bound.")
else:
print("Please specify the a value")
if __name__ == '__main__':
import sys
print("\n********* Fibonacci Series Using Dynamic Programming ************\n")
# For python 2.x and 3.x compatibility: 3.x has not raw_input builtin
# otherwise 2.x's input builtin function is too "smart"
if sys.version_info.major < 3:
input_function = raw_input
else:
input_function = input
print("\n Enter the upper limit for the fibonacci sequence: ", end="")
try:
N = eval(input())
fib = Fibonacci(N)
print(
"\n********* Enter different values to get the corresponding fibonacci sequence, enter any negative number to exit. ************\n")
while True:
print("Enter value: ", end=" ")
i = eval(input())
if i < 0:
print("\n********* Good Bye!! ************\n")
break
fib.get(i)
except NameError:
print("\nInvalid input, please try again.")
except NameError:
print("\n********* Invalid input, good bye!! ************\n")