Round 1
Questions: Currently, the utility generates only special strings. A string is special if there are no matching adjacent characters. Given a string s of length n, generate a special string of length n that is lexicographically greater than s. If multiple such special strings exist, return the smallest string among them.
- Special String: A string is special if there are no two adjacent characters that are the same.
- Lexicographical Order: This is a generalization of the way words are alphabetically ordered in dictionaries. For example, "abc" is lexicographically smaller than "abd" because 'c' comes before 'd' in the alphabet.
A string a is lexicographically smaller than a string b if and only if one of the following holds:
- a is a prefix of b, but a is not equal to b. For example, "abc" is smaller than "abcd".
- In the first position where a and b differ, the character in a comes before the character in b in the alphabet. For example, "abc" is smaller than "abd" because 'c' comes before 'd'.
Important Considerations:
- If the character is 'z', it is the last character in the alphabet and cannot be increased further. The string should not wrap around to 'a' after 'z'.
- The output string must not have any adjacent characters that are the same.
The lexicographically smallest special string that is greater than "abbd" is "abca".
Function Description: Complete the function getSpecialString in the editor below.
getSpecialString has the following parameter:
- s: the input string
Returns:
- string: the lexicographically smallest string that is greater than s. If no such special string exists, return "-1".
Constraints:
- 1 <= |s| <= 10^6
- s consists of lowercase English letters only.
Sample Input:
abccde
Sample Output:
abcdab
Explanation: s = "abccde" Some of the special strings that are lexicographically greater than s are "abcdde", "abcdab", "abcdbc".
Sample Case 1: Sample Input For Custom Testing:
zzab
Sample Output:
-1
Explanation: s = "zzab" There is no special string of length 4 that is lexicographically greater than s.
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