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.

思路：创建两个map，进行匹配。

class Solution {
public:
    bool isIsomorphic(string s, string t) {
        if (s.size() != t.size()) return false;
        map<char, int> sdict, tdict;
        for (int i = 0, n = s.size(); i < n; i++)
        {
            if (sdict[s[i]] != tdict[t[i]])
                return false;
            sdict[s[i]] = tdict[t[i]] = i + 1;
        }
        return true;
    }
};