力扣：剑指 Offer II 015. 字符串中的所有变位词

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;


public class Solution {
    public static void main(String[] args) {
        Solution solution = new Solution();
        String s = "cbaebabacd", p = "abc";
        System.out.println(solution.findAnagrams(s, p));
    }

    
    public List findAnagrams(String s, String p) {
        List res = new ArrayList<>();
        int m = s.length(), n = p.length();
        if (m < n){
            return res;
        }

        int[] sArr = new int[26];
        int[] pArr = new int[26];

        for (int i = 0; i < n; i++){
            sArr[s.charAt(i) - 'a']++;
            pArr[p.charAt(i) - 'a']++;
        }
        if (Arrays.equals(sArr, pArr)){
            res.add(0);
        }

        // 滑动窗口进行比较
        for (int i = 0; i < m - n; i++){
            sArr[s.charAt(i) - 'a']--;
            sArr[s.charAt(i + n) - 'a']++;
            if (Arrays.equals(sArr, pArr)){
                res.add(i + 1);
            }
        }
        return res;
    }

}