Count Complete Substrings
You are given a string word and an integer k.
A substring s of word is complete if:
- Each character in
soccurs exactlyktimes. - The difference between two adjacent characters is at most
2. That is, for any two adjacent charactersc1andc2ins, the absolute difference in their positions in the alphabet is at most2.
Return the number of complete substrings of word.
A substring is a non-empty contiguous sequence of characters in a string.
Example 1
Input
word = "igigee", k = 2Output
3The complete substrings where each character appears exactly twice and the difference between adjacent characters is at most 2 are igig, ee, and igigee.
Example 2
Input
word = "aaabbbccc", k = 3Output
6The complete substrings where each character appears exactly three times and the difference between adjacent characters is at most 2 are aaa, bbb, ccc, aaabbb, bbbccc, and aaabbbccc.
Constraints
- 1 <= word.length <= 10^5
- word consists only of lowercase English letters.
- 1 <= k <= word.length