What is the optimal time complexity of solving Binary to Decimal conversion?

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 Binary to Decimal conversion?

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 Binary to Decimal conversion?

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 Binary to Decimal conversion?

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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Python BasicsEasy

Binary to Decimal conversion

Learn how to solve the 'Binary to Decimal conversion' problem. This detailed resource details brute force and optimized approaches.

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Problem Statement

Easy

Write a function binary_to_decimal(binary_str) that takes a string representing a binary number (containing only '0' and '1') and returns its decimal (base-10) integer equivalent.

Each digit in a binary number represents a power of 2, starting from the rightmost digit (2^0). For example, binary '1010' = 1×2³ + 0×2² + 1×2¹ + 0×2⁰ = 8 + 0 + 2 + 0 = 10.

Constraints

•1 <= len(binary_str) <= 20
•binary_str contains only '0' and '1'

Examples

Example 1

Input

binary_to_decimal('1010')

Output

Explanation

1×2³ + 0×2² + 1×2¹ + 0×2⁰ = 8 + 0 + 2 + 0 = 10.

Example 2

Input

binary_to_decimal('1111')

Output

Explanation

1×2³ + 1×2² + 1×2¹ + 1×2⁰ = 8 + 4 + 2 + 1 = 15.

Example 3

Input

binary_to_decimal('10000')

Output

Explanation

1×2⁴ = 16.

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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