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### by Sumit Chourasia | Sep 27, 2020 | Category :coding | Tags : algorithmडेटा-संरचनाआसानhash-tableleetcode #### Isomorphic Strings - Hash Table - Easy - LeetCode - मिनी टीवी

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.

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
Note:
You may assume both s and t have the same length.

``````public class Solution {
public bool IsIsomorphic(string s, string t) {

if(s.Length != t.Length){
return false;
}

var map1 = new Dictionary<char,char>();
var map2 = new Dictionary<char,char>();
for(int i=0;i<s.Length;i++){
if(map1.ContainsKey(s[i])){
map1[s[i]] = t[i];
}
else{
}

if(map2.ContainsKey(t[i])){
map2[t[i]] = s[i];
}
else{
}
}

for(int i=0;i<s.Length;i++){
if(map1[s[i]]!=t[i]){
return false;
}

if(map2[t[i]]!=s[i]){
return false;
}
}

return true;
}
}``````

Time Complexity: O(n)

Space Complexity: O(n)