What is the optimal time complexity of solving Counting number of days in a given month of a year?

The optimized solution achieves a time complexity of O(n) by using sorting, mathematical shortcuts, or hash table lookups.

What is the auxiliary space complexity for Counting number of days in a given month of a year?

The space complexity is O(1) since we only use a minimal/constant amount of extra memory for tracking variables (or auxiliary space if dynamic structures are allocated).

What are the typical edge cases we must handle in Counting number of days in a given month of a year?

Key edge cases include empty collections, negative or large bounds causing integer overflow, arrays with only one element, or inputs where target criteria are not met.

How can we optimize the brute force approach for Counting number of days in a given month of a year?

Brute force methods often inspect all possible combinations. We optimize this by sorting the input list to enable binary search, or tracking processed items in a set to avoid redundant nested loop lookups.

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Counting number of days in a given month of a year

Learn how to solve the 'Counting number of days in a given month of a year' problem. This detailed resource details brute force and optimized approaches.

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Problem Statement

Easy

Write a function days_in_month(month, year) that takes an integer month (1-12) and an integer year, and returns the number of days in that month.

Remember:

- Months with 31 days: January(1), March(3), May(5), July(7), August(8), October(10), December(12)

- Months with 30 days: April(4), June(6), September(9), November(11)

- February(2): 28 days normally, 29 days in a leap year

- Leap year: divisible by 4, but not by 100, unless also divisible by 400

Constraints

•1 <= month <= 12
•1 <= year <= 9999

Examples

Example 1

Input

days_in_month(2, 2024)

Output

Explanation

2024 is divisible by 4 and not by 100, so it's a leap year. February has 29 days.

Example 2

Input

days_in_month(1, 2023)

Output

Explanation

January always has 31 days regardless of the year.

Example 3

Input

days_in_month(2, 1900)

Output

Explanation

1900 is divisible by 100 but not by 400, so it's NOT a leap year. February has 28 days.

Need a Hint?

Use simple arithmetic operators (like modulo `%`, division `//`), conditional checks, or loops to inspect number properties.

Edge Cases to Watch

Empty list or null input variables
Single item lists/arrays
Extremely large input bounds causing integer or stack overflow

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