Find start indices of anagram substrings

You are given two strings:

• s : the text string
• p : the pattern string

Return a list of all starting indices i such that the substring s[i : i + len(p)] is a permutation (an anagram) of p. The indices can be returned in increasing order.

Input

• s and p contain only lowercase English letters.

Output

• An array/list of integers: all valid starting indices.

Examples

1. s = "cbaebabacd" , p = "abc" → [0, 6]
   • s[0:3] = "cba" is an anagram of "abc"
   • s[6:9] = "bac" is an anagram of "abc"
2. s = "abab" , p = "ab" → [0, 1, 2]

Constraints

• 1 <= len(s) <= 3 * 10^4
• 1 <= len(p) <= 3 * 10^4
• len(p) <= len(s)