Given two strings s1 and s2, write a function to return true if s2 contains the permutation of s1. In other words, one of the first string's permutations is the substring of the second string.

Example 1:

Input: s1 = "ab" s2 = "eidbaooo"

Output: True

Explanation: s2 contains one permutation of s1 ("ba").

Example 2:

Input:s1= "ab" s2 = "eidboaoo"

Output: False

Note:

The input strings only contain lower case letters.

The length of both given strings is in range [1, 10,000].

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class Solution {    public boolean checkInclusion(String s1, String s2) {        if (s1 == null || s2 == null || s1.length() > s2.length()) {            return false;        }        int l1 = s1.length();        int l2 = s2.length();        int[] c1 = new int[26];        int[] c2 = new int[26];        for(char c : s1.toCharArray()){            c1[c-'a']++;        }        for(int i=0; i
    
     =l1){                c2[s2.charAt(i-l1)-'a']--;            }            c2[s2.charAt(i)-'a']++;            if(Arrays.equals(c1,c2)){                return true;            }        }        return false;    }}