JuniorString
Largest 3-Same-Digit Number in String
You are given a string num representing a large integer. An integer is good if it meets the following conditions:
- It is a substring of
numwith length3. - It consists of only one unique digit.
Return the maximum good integer as a string, or an empty string "" if no such integer exists.
Note:
- A substring is a contiguous sequence of characters within a string.
- There may be leading zeroes in
numor a good integer.
Example 1
Input
num = "6777133339"Output
"777"There are two distinct good integers, "777" and "333"; "777" is the largest, so it is returned.
Example 2
Input
num = "2300019"Output
"000""000" is the only good integer.
Constraints
- 3 <= num.length <= 1000
- num only consists of digits.