Level 2 — RecallIntroduction to Programming (Python)

Introduction to Programming (Python)

40 marksprintable — key stays hidden on paper

Level 2 — Recall & Standard Problems

Time: 30 minutes Total Marks: 40

Answer all questions. Assume Python 3. Where output is asked, write exactly what Python prints.

Q1. Define the following in one line each, and give the Python literal for a value of that type: (a) int, (b) str, (c) bool, (d) NoneType. (4 marks)

Q2. Predict the output of each expression: (6 marks)

(a) 17 // 5
(b) 17 % 5
(c) 2 ** 5
(d) 7 / 2
(e) -7 // 2
(f) 10 % 3

Q3. State whether each is a valid Python variable name. If invalid, give the reason. (4 marks)

(a) 2nd_value
(b) _total
(c) my-name
(d) class

Q4. Given s = "Programming", write the value produced by: (5 marks)

(a) s[0]
(b) s[-1]
(c) s[0:4]
(d) s[::2]
(e) len(s)

Q5. Evaluate these logical/comparison expressions to True or False: (4 marks)

(a) 5 > 3 and 2 == 2
(b) not (4 < 2)
(c) 3 != 3 or 1 < 0
(d) True and not False

Q6. Write the output: (4 marks)

nums = [4, 1, 3, 1, 2]
nums.append(5)
nums.sort()
print(nums)
print(nums.count(1))

Q7. Write a for loop using range() that prints the sum of all integers from 1 to 100 (inclusive). Then state the numeric value of that sum. (4 marks)

Q8. Write the output of this f-string program: (3 marks)

name = "Ada"
age = 36
print(f"{name} is {age} years old, next year {age + 1}")

Q9. Write a recursive Python function fact(n) that returns n!. Clearly mark the base case and recursive case. State the value of fact(5). (4 marks)

Q10. Given d = {"a": 1, "b": 2}, write what each returns: (2 marks)

(a) d.get("c", 0)
(b) list(d.keys())

Answer keyMark scheme & solutions

Q1. (4 marks) — 1 mark each (definition + valid literal)

(a) int: whole number without decimal — e.g. 7.
(b) str: ordered sequence of characters (text) — e.g. "hi".
(c) bool: truth value, True/False — e.g. True.
(d) NoneType: the type of the absence-of-value object — literal None. Why: recall of core built-in types (1.2.4).

Q2. (6 marks) — 1 each

(a) 3 (floor division)
(b) 2 (remainder)
(c) 32 ( $2^5$ )
(d) 3.5 (true division always float)
(e) -4 (floor division rounds toward −∞)
(f) 1 Why: // floors toward negative infinity, so -7//2 = floor(-3.5) = -4 (1.2.6).

Q3. (4 marks) — 1 each

(a) Invalid — cannot start with a digit.
(b) Valid — leading underscore allowed.
(c) Invalid — hyphen not allowed (parsed as subtraction).
(d) Invalid — class is a reserved keyword. Why: naming rules — letters/digits/underscore, not starting with digit, no keywords (1.2.3).

Q4. (5 marks) — 1 each. s = "Programming" (indices 0–10)

(a) 'P'
(b) 'g'
(c) 'Prog' (indices 0,1,2,3)
(d) 'Pormig' (every 2nd char: P,o,r,m,i,g)
(e) 11 Why: slicing stop is exclusive; step 2 takes indices 0,2,4,6,8,10 (1.2.11).

Q5. (4 marks) — 1 each

(a) True
(b) True (4<2 is False, not False = True)
(c) False (both operands False)
(d) True Why: precedence not > and > or; short-circuit rules (1.2.7, 1.2.8).

Q6. (4 marks)

After append: [4,1,3,1,2,5]; after sort: [1,1,2,3,4,5].
Output line 1: [1, 1, 2, 3, 4, 5] (2 marks)
Output line 2: 2 (count of 1) (2 marks) Why: sort() mutates in place ascending; count tallies occurrences (1.2.22).

Q7. (4 marks)

total = 0
for i in range(1, 101):   # 1 to 100 inclusive
    total += i
print(total)

Correct loop with range(1,101): 2 marks
Correct accumulation/print: 1 mark
Value 5050: 1 mark Why: $\sum_{1}^{100} = \frac{100\cdot101}{2}=5050$ (1.2.19).

Q8. (3 marks) Output: Ada is 36 years old, next year 37

Correct substitution of name/age: 2 marks; correct age+1=37: 1 mark. Why: f-strings evaluate embedded expressions (1.2.13).

Q9. (4 marks)

def fact(n):
    if n == 0 or n == 1:   # base case
        return 1
    return n * fact(n - 1) # recursive case

Base case marked: 1 mark
Recursive case correct: 2 marks
fact(5) = 120: 1 mark Why: $5!=5\cdot4\cdot3\cdot2\cdot1=120$ ; base case stops recursion (1.2.38).

Q10. (2 marks) — 1 each

(a) 0 (key absent → default returned)
(b) ['a', 'b'] Why: get returns default when key missing; keys() preserves insertion order (1.2.24).

[
  {"claim":"17//5=3 and 17%5=2 and 2**5=32", "code":"result = (17//5==3) and (17%5==2) and (2**5==32)"},
  {"claim":"-7//2 == -4", "code":"result = (-7//2 == -4)"},
  {"claim":"sum 1..100 = 5050", "code":"result = (sum(range(1,101))==5050)"},
  {"claim":"fact(5)=120", "code":"from sympy import factorial\nresult = (factorial(5)==120)"},
  {"claim":"slice 'Programming'[::2]=='Pormig'", "code":"result = ('Programming'[::2]=='Pormig')"}
]