205. Isomorphic Strings

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.

Note:
You may assume both s and t have the same length.

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Solution:

Tips:

record the character in the two strings respectively.

Java Code:

public class Solution {
    public boolean isIsomorphic(String s, String t) {
        int[] sTable = new int[256];
        int[] tTable = new int[256];
        
        for (int i = 0; i < s.length(); i++) {
            if (sTable[s.charAt(i)] != tTable[t.charAt(i)]) {
                return false;
            }
            sTable[s.charAt(i)] = i + 1;
            tTable[t.charAt(i)] = i + 1;
        }
        
        return true;
    }
}