Given two strings s and p, return an array of all the start indices of p's anagrams in s. You may return the answer in any order.
An Anagram is a word or phrase formed by rearranging the letters of a different word or phrase, typically using all the original letters exactly once.
Example 1:
Input: s = "cbaebabacd", p = "abc" Output: [0,6] Explanation: The substring with start index = 0 is "cba", which is an anagram of "abc". The substring with start index = 6 is "bac", which is an anagram of "abc".
Example 2:
Input: s = "abab", p = "ab" Output: [0,1,2] Explanation: The substring with start index = 0 is "ab", which is an anagram of "ab". The substring with start index = 1 is "ba", which is an anagram of "ab". The substring with start index = 2 is "ab", which is an anagram of "ab".
Constraints:
1 <= s.length, p.length <= 3 * 104s and p consist of lowercase English letters.class Solution {
public:
vector<int> findAnagrams(string s, string p) {
vector<int> pHash(26, 0), winHash(26, 0);
vector<int> ans;
if(s.length()<p.length())
return ans;
for(auto c: p)
pHash[c-'a']++;
for(int lt=0, rt=0; rt<p.length(); rt++)
winHash[s[rt]-'a']++;
if(winHash==pHash)
ans.push_back(0);
for(int lt=1, rt=p.length(); rt<s.length();lt++, rt++){
winHash[s[lt-1]-'a']--;
winHash[s[rt]-'a']++;
if(winHash==pHash)
ans.push_back(lt);
}
return ans;
}
};