leetcode 205 Isomorphic Strings

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.

Subscribe to see which companies asked this question

class Solution {
public:
bool isIsomorphic(string s, string t) {
vector<char> maps(255, 0);
vector<int> visited(255, 0);

for(int i = 0; i < s.length(); i++) {
if(maps[s[i]]!=0) {
if(maps[s[i]] != t[i]) return false;
} else {
if(visited[t[i]] == 1) return false;

maps[s[i]]=t[i];
visited[t[i]]=1;
}
}

return true;
}
}