find-all-anagrams-in-a-string

https://leetcode.com/problems/find-all-anagrams-in-a-string/

package com.company;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

class Solution {
    public List<Integer> findAnagrams(String s, String p) {
        int[] smap = new int[26];
        int[] pmap = new int[26];
        int plen = p.length();
        int slen = s.length();

        for (int i=0; i<plen; i++) {
            pmap[p.charAt(i)-'a']++;
        }

        List<Integer> lst = new ArrayList<>();
        int count = 0;
        for (int i=0; i<plen&&i<slen; i++) {
            int xx = s.charAt(i) - 'a';
            if (pmap[xx] > 0) {
                smap[xx]++;
                if (smap[xx] <= pmap[xx]) {
                    count++;
                }
            }
        }
        if (count == plen) {
            lst.add(0);
        }
        for (int i=plen; i<slen; i++) {
            int yy = s.charAt(i-plen) - 'a';
            if (smap[yy] > 0) {
                smap[yy]--;
                if (smap[yy] < pmap[yy]) {
                    count--;
                }
            }
            int xx = s.charAt(i) - 'a';
            if (pmap[xx] > 0) {
                smap[xx]++;
                if (smap[xx] <= pmap[xx]) {
                    count++;
                }
            }
            if (count == plen) {
                lst.add(i-plen+1);
            }
        }
        return lst;
    }
}

public class Main {

    public static void main(String[] args) {
        // write your code here
        System.out.println("Hello");
        Solution solution = new Solution();

        List<Integer> ret = solution.findAnagrams("abab", "ab");
        System.out.printf("Result is len %d\n", ret.size());
        Iterator<Integer> iter = ret.iterator();
        while (iter.hasNext()) {
            System.out.printf("%d;", iter.next());
        }
        System.out.println();

    }
}