FilesExpand file tree

 master

/

IsomorphicStrings.java

Copy path

Blame

More file actions

Blame

More file actions

Latest commit

 

History

History

History

53 lines (50 loc) · 1.56 KB

 master

/

IsomorphicStrings.java

Copy path

Top

File metadata and controls

• Code
• Blame

53 lines (50 loc) · 1.56 KB

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

package string;

import java.util.HashMap;

import java.util.Map;

/**

* Created by gouthamvidyapradhan on 11/04/2018. Given two strings s and t, determine if they are

* isomorphic.

*

* <p>Two strings are isomorphic if the characters in s can be replaced to get t.

*

* <p>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.

*

* <p>For example, Given "egg", "add", return true.

*

* <p>Given "foo", "bar", return false.

*

* <p>Given "paper", "title", return true.

*

* <p>Note: You may assume both s and t have the same length. Solution O(N): Maintain two hashmaps

* and compare character by character.

*/

public class IsomorphicStrings {

/**

* Main method

*

* @param args

* @throws Exception

*/

public static void main(String[] args) throws Exception {

System.out.println(new IsomorphicStrings().isIsomorphic("abc", "dea"));

}

public boolean isIsomorphic(String s, String t) {

if (s.length() != t.length()) return false;

Map<Character, Character> first = new HashMap<>();

Map<Character, Character> second = new HashMap<>();

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

char c = s.charAt(i);

if (first.containsKey(c)) {

char secondC = first.get(c);

if (t.charAt(i) != secondC) return false;

} else {

first.put(c, t.charAt(i));

if (second.containsKey(t.charAt(i))) return false;

second.put(t.charAt(i), c);

}

}

return true;

}

}