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Isomorphic Strings

Problem Statement​

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.

Leetcode Link

Example 1:​

Input: s = "egg", t = "add"
Output: true

Example 2:​

Input: s = "foo", t = "bar"
Output: false

Example 3:​

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

Code​

Python
class Solution:
    def isIsomorphic(self, s: str, t: str) -> bool:
        return len(set(s))==len(set(zip(s,t)))==len(set(t))
C++
class Solution {
public:
    bool isIsomorphic(string s, string t) {
        unordered_map<char, char> m1, m2;
        for (int i = 0; i < s.size(); i++) {
            if (!m1.count(s[i]) && !m2.count(t[i]))
                m1[s[i]] = t[i];m2[t[i]] = s[i];
             else
                    if (m1[s[i]] != t[i] || m2[t[i]] != s[i])  return false;
        }
        return true;
    }
};