Positive or Negative number
Detailed guide and Python implementation for the 'Positive or Negative number' problem.
1. Concept Overview
The 'Positive or Negative number' problem is a key challenge in the Basics section.
This implementation focuses on easy-level logic in Python.
We prioritize technical accuracy and code readability in our provided solutions.
2. Real-World Applications
3. Visual Intuition
Visualizing the logic flow for Positive or Negative number.
4. Prerequisites
5. Step-by-Step Thinking
1. Understand the problem
Read the problem statement for Positive or Negative number carefully.
2. Formulate brute force
Draft a simple iterative solution.
3. Identify inefficiency
Look for redundant calculations.
4. Optimize search path
Use hashing or sorting to speed up the process.
5. Final Implementation
Clean up the code for production standards.
Problem Statement
Write a function check_sign(n) that takes an integer n and returns the string "Positive" if n is greater than zero, "Negative" if n is less than zero, or "Zero" if n is exactly zero.
- •-10^9 <= n <= 10^9
Examples
n = 5
"Positive"
5 is greater than 0, so we return "Positive".
n = -3
"Negative"
-3 is less than 0, so we return "Negative".
n = 0
"Zero"
0 is neither positive nor negative, so we return "Zero".
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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Interview Insights & Variations
Complexity Analysis Breakdown
Why Time: Directly evaluates all possibilities.
Why Space: Uses standard local memory.
Why Time: Optimized paths reduce total operations.
Why Space: May trade memory for speed.
Optimized Solution Python Code
Optimized Solution Python Code
def check_number_opt(n):
return "Positive" if n > 0 else "Negative" if n < 0 else "Zero"Brute Force Code (Spoiler Guarded)
Brute Force Code (Spoiler Guarded)
def check_number(n):
if n > 0: return "Positive"
elif n < 0: return "Negative"
else: return "Zero"Algorithm Pattern Checklist
When dealing with Basics data patterns.
Core Prerequisites
Revision Key Notes
Common Mistakes & Pitfalls
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