How do you solve Create a New Column on LeetCode?

Create a New Column (LeetCode #2881) can be solved using Brute Force or Optimal Solution. The optimal approach is Optimal Solution with O(n) time complexity and O(n) space complexity. Key insight: Vectorized operations can significantly improve performance.

What is the brute force solution for Create a New Column?

The brute force approach for Create a New Column is Brute Force, with O(n) time complexity and O(n) space complexity. In this approach, we will manually iterate through each employee's salary and calculate the bonus by doubling it. This is straightforward but inefficient for larger datasets. The optimal Optimal Solution approach improves this to O(n).

What are the interview tips for Create a New Column?

Always consider built-in functions for efficiency. Explain your thought process clearly when coding. Test your code with edge cases to ensure robustness.

What are common mistakes when solving Create a New Column?

Overcomplicating the solution with unnecessary loops. Not utilizing built-in functions for operations.

#2881

Create a New Column

Easy

ArrayDataFrame Manipulation

LeetCode ↗

Approaches

Brute ForceOptimal

Complexity Comparison

	Brute Force	Optimal Solution★
Time	O(n)	O(n)
Space	O(n)	O(n)

💡

Intuition

Time O(n)Space O(n)

This approach leverages vectorized operations provided by libraries like pandas in Python, which allows us to perform operations on entire columns at once, making it much faster and more efficient.

⚙️

Algorithm

2 steps

1Step 1: Use the DataFrame's built-in operations to directly create the bonus column by multiplying the salary column by 2.
2Step 2: This operation is done in a single line, which is optimized for performance.

solution.py5 lines

1import pandas as pd
2
3df = pd.DataFrame({'name': ['Piper', 'Grace', 'Georgia', 'Willow', 'Finn', 'Thomas'], 'salary': [4548, 28150, 1103, 6593, 74576, 24433]})
4df['bonus'] = df['salary'] * 2
5print(df)

ℹ

Complexity note: The time complexity remains O(n) since we are still iterating through the salaries, but the operations are optimized. The space complexity is O(n) due to the new column for bonuses.

1Vectorized operations can significantly improve performance.
2Understanding DataFrame operations is crucial for efficient data manipulation.

Solutions and explanations are original Tejav content. Problem titles © LeetCode — use the LeetCode button above for the full problem statement.