1 class Solution {
2 public List<Integer> findAnagrams(String s, String p) {
3 List<Integer> res = new ArrayList<>();
4 if(s.length() == 0 || s.length() < p.length()) return res;
5 int[] map = new int[128];
6 int count = 0;
7 for(char c : p.toCharArray()){
8 map[c]++;
9 count++;
10 }
11 int begin = 0, end = 0;
12 while(end < s.length()){
13 if(end < p.length()-1){
14 if(map[s.charAt(end)]-- > 0 ) count--;
15 end++;
16 }else{
17 if(map[s.charAt(end)]-- > 0) count--;
18 end++;
19 if(count == 0) res.add(begin);
20 // System.out.println(count);
21 if(map[s.charAt(begin)]++ >= 0) count++; // >= 0 !!! 注意
22 begin++;
23 }
24 }
25 return res;
26
27 }
28 }
