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 ", ret.size()); Iterator<Integer> iter = ret.iterator(); while (iter.hasNext()) { System.out.printf("%d;", iter.next()); } System.out.println(); } }