205. Isomorphic Strings

Given two strings s and t, determine if they are isomorphic.

Two strings s and t 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.

Example 1:
Input: s = "egg", t = "add"
Output: true
Explanation:
The strings s and t can be made identical by:

• Mapping 'e' to 'a'.
• Mapping 'g' to 'd'.

Example 2:
Input: s = "foo", t = "bar"
Output: false
Explanation:
The strings s and t can not be made identical as 'o' needs to be mapped to both 'a' and 'r'.

Example 3:
Input: s = "paper", t = "title"
Output: true

def isIsomorphic(self, s: str, t: str) -> bool:
	l = len(s)
	d = {}
	for i in range(l):
		if s[i] in d:
			if d[s[i]] != t[i]:
				return False
		else:
			if t[i] in d.values():
				return False
			d[s[i]] = t[i] 
	return True