No205.java

packageAlgorithm.leetcode.String;

importjava.util.HashMap;
importjava.util.Map;

publicclassNo205 {
publicbooleanisIsomorphic(Strings, Stringt) {
if (s.length() <= 1 || s == null) {
returntrue;
 }
Map<Character, Character> hashMap = newHashMap<Character, Character>();
for (inti = 0; i < s.length(); i++) {
chara = s.charAt(i);
charb = t.charAt(i);
if (hashMap.containsKey(a)) {
if (hashMap.get(a).equals(b)) {
continue;
 } else {
returnfalse;
 }
 } else {
if (!hashMap.containsValue(b)) {
hashMap.put(a, b);
 } else {
returnfalse;
 }
 }
 }
returntrue;
 }
}