LeetCode 438

package leetcode;

import java.util.Arrays;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;

public class SolutionFor438 {
    public List<Integer> findAnagrams(String s, String p) {
        LinkedList<Integer> ans = new LinkedList<>();
        if(s.length() < p.length()) {
            return ans;
        }
        else if(s.length() == p.length()) {
            if(s.equals(p)) ans.add(0);
        }
        else {
            int[] temp = new int[26];
            Arrays.fill(temp,0);
            for(Character c:p.toCharArray()) {
                temp[c-'a']++;
            }
            for(int i = 0;i < s.length(); ++i) {
                temp[s.charAt(i)-'a']--;
                if(i >= p.length()) {
                    temp[s.charAt(i - p.length()) - 'a']++;
                }
                boolean ok = true;
                for(int j = 0;j < 26; ++j) {
                    if(temp[j] != 0) {
                        ok = false;
                        break;
                    }
                }
                if(ok == true) ans.add(i-p.length()+1);
            }
        }
        return ans;
    }

    public static void main(String[] args) {
        String s = "abab";
        String p = "ab";
        SolutionFor438 Sl = new SolutionFor438();
        System.out.println(Sl.findAnagrams(s,p));
    }
}