static boolean isIsomorphic(String s, String t) { if(s.length() != t.length()) return false; int[] s1 = new int[256]; int[] s2 = new int[256]; for(int i = 0; i < s.length(); i++) { if(s1[s.charAt(i)] != s2[t.charAt(i)]) return false; s1[s.charAt(i)] = s2[t.charAt(i)] = i + 1; } return true; } Language used f