In Python what is slicing?
Interviewer Expectations for this Question
01
Core Competency
Assesses fundamental understanding of Python conventions, runtime behavior, and memory/performance considerations.
02
Evaluation Criteria
Hiring managers look for precision, avoidance of ambiguous jargon, and ability to explain trade-offs under real production conditions.
Comprehensive Model Answer
Verified Solution
Slicing is a Python mechanism for extracting a sub-sequence from a sequence data type (such as a list, tuple, or str) using extended indexing notation:
### Syntax:sequence[start:stop:step]
start: Zero-based beginning index (inclusive). Defaults to 0.stop: Ending index (exclusive). Defaults to sequence length.step: Stride / increment value between indices. Defaults to 1.
### Practical Examples:
data = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
print(data[2:6]) # [2, 3, 4, 5] (sublist from index 2 to 5)
print(data[:4]) # [0, 1, 2, 3] (first 4 items)
print(data[6:]) # [6, 7, 8, 9] (from index 6 to end)
print(data[::2]) # [0, 2, 4, 6, 8] (every second item)
print(data[::-1]) # [9, 8, 7, 6, 5, 4, 3, 2, 1, 0] (reverse copy)
Slicing creates a new shallow copy of the requested elements without modifying the original sequence.
Candidate Response Strategy & Interview Tips
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