Isomorphic Strings

Author: parshva45

Isomorphic Strings.js

@@ -0,0 +1,38 @@
+/*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.*/
+
+/**
+ * @param {string} s
+ * @param {string} t
+ * @return {boolean}
+ */
+var isIsomorphic = function(s, t) {
+    sdict = {}
+    tdict = {}
+    for(i=0; i<s.length; i++){
+        if(s[i] in sdict){
+            if(!t[i] in tdict || sdict[s[i]] != tdict[t[i]])
+                return false
+        }
+        else{
+            if(t[i] in tdict)
+                return false
+            sdict[s[i]] = i
+            tdict[t[i]] = i
+        }
+    }
+    return true
+};