Check if two given strings are isomorphic to each other

Check if two given strings are isomorphic to each other

Given two strings s and t, determine if they are isomorphic. Two strings are isomorphic if the characters in s can be replaced to get t.

All occurrences of a character must be replaced with another character while preserving the order of characters. No two characters may map to the same character but a character may map to itself.

For example,

Given "egg", "add", return true.

Given "foo", "bar", return false.

Given "paper", "title", return true.

public class TestIsomorphic {

      public static void main(String[] args) {

            String str1 = "abb";

            String str2 = "axx";

            boolean res = TestIsomorphic.checkIsomorphic(str1,str2);

            System.out.println(res);

      }

      static boolean checkIsomorphic(String str1, String str2) {

            int length = str1.length();

            /* length of both strings must be same */

            if (length != str2.length()) {

                  return false;

            }

            // To mark visited characters in str2

            char visited[] = new char[26];

            for (int i = 0; i < visited.length; i++) {

                  visited[i] = '#';

            }

            char[] strArr1 = str1.toCharArray();

            char[] strArr2 = str2.toCharArray();

            // Process all characters one by on

            for (int i = 0; i<length; i++) {

                  char ch = visited[strArr1[i]-'a'];

                  if(ch=='#') {

                        visited[strArr1[i]-'a'] = strArr2[i];

                  } else if (ch != strArr2[i]) {

                        return false;                      

                  }

            }

            return true;

      }

}

Output: true