0205-isomorphic-strings.java

classSolution {
publicbooleanisIsomorphic(Strings, Stringt) {
// Needs bidirectional mapping from s <--> t
if(s.length() != t.length()) {
returnfalse;
 }

Map<Character, Character> mapSourceToDest = newHashMap<>();
Map<Character, Character> mapDestToSource = newHashMap<>();

intlen = s.length();
for(inti=0; i<len; i++) {
charsourceChar = s.charAt(i), destChar = t.charAt(i);
charsourceReturn = mapSourceToDest.getOrDefault(sourceChar, destChar);
if(sourceReturn != destChar) {
returnfalse;
 }
mapSourceToDest.put(sourceChar, destChar);

chardestReturn = mapDestToSource.getOrDefault(destChar, sourceChar);
if(destReturn != sourceChar) {
returnfalse;
 }
mapDestToSource.put(destChar, sourceChar);
 }

returntrue;
 }
}