Isomorphic Strings

Problem Link:

https://leetcode.com/problems/isomorphic-strings/description/

My approach:

We have to do bi-directional mapping so I used two hashmaps.

Code:

// TIME COMPLEXITY : O(N)
// SPACE COMPLEXITY : O(1) , Hashmaps will never exceed the size of 26
//                           no matter the size of 's' and 't'.

class Solution {
public:
    bool isIsomorphic(string s, string t) {

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

        int n = s.size();
        unordered_map<char,char> map;
        unordered_map<char,char> map1;

        for(int i=0;i<n;i++){

// to avoid collision from s to t
            if(map.count(t[i])>0 && map[t[i]]!=s[i]){
                return false;
            }
            else{
                map[t[i]] = s[i];
            }
// to avoid collison from t to s
            if(map1.count(s[i])>0 && map1[s[i]]!=t[i]){
                return false;
            }
            else{
                map1[s[i]] = t[i];
            }
        }

        return true;
    }
};