Week-4

1. Consider the following Python function.
def mystery(l):
    if l == []:
        return(l)
    else:
        return(mystery(l[1:])+l[:1])
What does mystery([22,14,19,65,82,55]) return?

[55, 82, 65, 19, 14, 22]

2. What is the value of pairs after the following assignment?
pairs = [ (x,y) for x in range(4,1,-1) for y in range(5,1,-1) if (x+y)%3 == 0 ]

[(4, 5), (4, 2), (3, 3), (2, 4)]

3. Consider the following dictionary.
wickets = {"Tests":{"Kumble":[3,5,2,3],"Srinath":[4,4,1,0],"Prasad":[2,1,7,4]},"ODI":{"Kumble":[2,0],"Srinath":[1,2]}}
Which of the following statements does not generate an error?
 wickets["ODI"]["Prasad"][0:] = [4,4]
 wickets["ODI"]["Prasad"].extend([4,4])
 wickets["ODI"]["Prasad"] = [4,4]
 wickets["ODI"]["Prasad"] = wickets["ODI"]["Prasad"] + [4,4]

wickets["ODI"]["Prasad"] = [4,4]

4. Assume that hundreds has been initialized as an empty dictionary:
hundreds = {}
Which of the following generates an error?
 hundreds["Tendulkar, international"] = 100
 hundreds["Tendulkar"] = {"international":100}
 hundreds[("Tendulkar","international")] = 100
 hundreds[["Tendulkar","international"]] = 100

hundreds[["Tendulkar","international"]] = 100