Permutation String

Sneha Michelle,Fri Jun 23 2023•Sliding Window

Problem Statement

Two strings are given. We need to find if there exists a permutation of the second string in the first string.
Eg: s1: ab, s2: eidbaooo. returns true because ba exists in the string.

Algorithm

Convert the string into a character array
Sort the array
Make it into a new string
for i<second string - first string,
- take substring ( i, i+s1.length())
- make into character array
- sort the array
- make it into string
  - is this string and first string same? return true
return false

Code

class Solution {
    public boolean checkInclusion(String s1, String s2) {
    
        char[] s1temparr = s1.toCharArray();
        Arrays.sort(s1temparr);
        String sorteds1 = new String(s1temparr);
 
        for (int i=0;i<s2.length()-s1.length()+1;i++){
            String temp = s2.substring(i, i+s1.length());
            char[] temparray = temp.toCharArray();
            Arrays.sort(temparray);
            String sortedarr = new String(temparray);
            if (sorteds1.equals(sortedarr)){
                return true;
            }
        }
 
        return false;
 
 
    }
}