Merge pull request #31 from akshaysharma096/master

Fibonnacci Sequence using Dynamic Programming.

dynamic_programming/fibonacci.py

@@ -0,0 +1,54 @@
+"""
+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")