Stack · Class 12 · CBSE · Science Computer Science
Consider the following Python code: s = [] def push(x): s.append(x) def popitem(): if len(s) == 0: return "Underflow" return s.pop() push(10) push(20…
Practice question from Stack (Class 12 · CBSE · Science Computer Science), with the correct answer and a step-by-step solution.
hard · MCQ · Q-3FD64D
Consider the following Python code: s = [] def push(x): s.append(x) def pop_item(): if len(s) == 0: return "Underflow" return s.pop() push(10) push(20) push(30) a = pop_item() push(40) b = pop_item() print(a, b, s[-1]) What will be printed?
- A.10 20 30
- B.30 40 20Correct answer
- C.30 20 40
- D.40 30 20
Solution
The first pop removes 30, so a becomes 30. After 40 is pushed, the next pop removes 40, so b becomes 40; the remaining stack is [10, 20], whose top is 20.
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