Problem Statement

Given a large integer num represented as string, return the largest-valued odd integer (represented as a string) that is a non-empty substring of num. If no such number exists, the result should be an empty string.

A substring is defined as a contiguous sequence of characters within a string.

Examples

• Example 1:

  • Input: num = "238946"
  • Expected Output: "2389"
  • Justification: The largest odd number in the string is "2389".

• Example 2:

  • Input: num = "2804"
  • Expected Output: ""
  • Justification: Since there are no odd numbers in the input string, the output is an empty string.

• Example 3:

  • Input: num = "13579"
  • Expected Output: "13579"
  • Justification: The entire input string is the largest odd number itself, as all digits are odd.

Try it yourself

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