Question

1.Write a function which takes in a dictionary are returns the sum of the keys plus the sum of the values, but only if all the keys and all the values are integers. Otherwise it returns False.

>>>f({'a':1,'b':4,'c':7,'d':11})
False
>>>f({1:2,3:4,5:6,7:8})
36


2.Write a function to quickly compute the recaman sequence.


3. The Hofstadter Conway sequence is defined by a(1)=a(2)=1 and (for n>2 by) a(n)=a(a(n-1))+a(n-a(n-1)). Write a function to quickly compute this sequence.

>>> [hc(i) for i in range(1,20)]
[1, 1, 2, 2, 3, 4, 4, 4, 5, 6, 7, 7, 8, 8, 8, 8, 9, 10, 11]

Answer 1

Question 1

def f(dic):
    # if key / value is a string it returns a error
    try:
        # sum of all keys
        keys = sum(dic.keys())
        # sum of all values
        values = sum(dic.values())
        # sum of both keys and values
        sumAll = keys + values
        # returns sum
        return sumAll
    except:
        # if it is not a integer returns False
        return False

Code

Output

Question 2

def hc(n):
    # if n is less than 0 it is invalid so returns 0
    if n < 0:
        return 0
    # if n=1 and n=2 it returns 1
    if n <= 2:
        return 1
    # remaining values will follow the formula
    return hc(hc(n-1)) + hc(n - hc(n-1))

Code

Output