Q2: A Plus Abs B
def a_plus_abs_b(a, b):
"""Return a+abs(b), but without calling abs.
>>> a_plus_abs_b(2, 3)
5
>>> a_plus_abs_b(2, -3)
5
>>> # a check that you didn't change the return statement!
>>> import inspect, re
>>> re.findall(r'^\\s*(return .*)', inspect.getsource(a_plus_abs_b), re.M)
['return f(a, b)']
"""
if b < 0:
f = sub
else:
f = add
return f(a, b)
Q3: Two of Three
def two_of_three(x, y, z):
"""Return a*a + b*b, where a and b are the two smallest members of the
positive numbers x, y, and z.
>>> two_of_three(1, 2, 3)
5
>>> two_of_three(5, 3, 1)
10
>>> two_of_three(10, 2, 8)
68
>>> two_of_three(5, 5, 5)
50
>>> # check that your code consists of nothing but an expression (this docstring)
>>> # a return statement
>>> import inspect, ast
>>> [type(x).__name__ for x in ast.parse(inspect.getsource(two_of_three)).body[0].body]
['Expr', 'Return']
"""
return min(x,y,z)*min(x,y,z) + max(min(x,y),min(x,z),min(z,y))*max(min(x,y),min(x,z),min(z,y))
Q4: Largest Factor
def largest_factor(n):
"""Return the largest factor of n that is smaller than n.
>>> largest_factor(15) # factors are 1, 3, 5
5
>>> largest_factor(80) # factors are 1, 2, 4, 5, 8, 10, 16, 20, 40
40
>>> largest_factor(13) # factor is 1 since 13 is prime
1
"""
"*** YOUR CODE HERE ***"
a = n - 1
while a > 0:
if n % a == 0:
return a
a -= 1
Q5: If Function vs Statement
def if_function(condition, true_result, false_result):
"""Return true_result if condition is a true value, and
false_result otherwise.
>>> if_function(True, 2, 3)
2
>>> if_function(False, 2, 3)
3
>>> if_function(3==2, 'equal', 'not equal')
'not equal'
>>> if_function(3>2, 'bigger', 'smaller')
'bigger'
"""
if condition:
return true_result
else:
return false_result
def with_if_statement():
"""
>>> result = with_if_statement()
61A
>>> print(result)
None
"""
if cond():
return true_func()
else:
return false_func()
def with_if_function():
"""
>>> result = with_if_function()
Welcome to
61A
>>> print(result)
None
"""
return if_function(cond(), true_func(), false_func())
def cond():
"*** YOUR CODE HERE ***"
return False
def true_func():
"*** YOUR CODE HERE ***"
print("Welcome to")
def false_func():
"*** YOUR CODE HERE ***"
print("61A")
Q6: Hailstone
def hailstone(n):
“““Print the hailstone sequence starting at n and return its
length.
a = hailstone(10) 10 5 16 8 4 2 1 a 7 """ "*** YOUR CODE HERE ***" x = 1 while n != 1: if n % 2 == 0 : print(n) n = n // 2 else: print(n) n = n * 3 + 1 x += 1 pass print(n) return x