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Multiply Strings

Detailed guide and Python implementation for the 'Multiply Strings' problem.

Problem Statement

Easy

Given two non-negative integers num1 and num2 represented as strings, return the product of num1 and num2, also represented as a string.

Note: You must not use any built-in BigInteger library or convert the inputs to integer directly.

Implement a function multiply(num1: str, num2: str) -> str.

Constraints
  • 1 <= num1.length, num2.length <= 200
  • num1 and num2 consist of digits only
  • Both num1 and num2 do not contain any leading zero, except the number 0 itself

Examples

Example 1
Input
"2", "3"
Output
"6"
Explanation

2 * 3 = 6.

Example 2
Input
"123", "456"
Output
"56088"
Explanation

123 * 456 = 56088.

Need a Hint?
Consider using Math & Geometry-specific data structures like sets or heaps.
Edge Cases to Watch
  • Empty input structures
  • Single element inputs
  • Large numerical bounds

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