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.

class Solution {
public:
    bool isIsomorphic(string s, string t) {
        int len1=s.length();
        map<char,char> m;
        map<char,char> m2;
        for(int i=0;i<len1;i++){
            if(m.find(s[i])==m.end()&&m2.find(t[i])==m2.end()){
                m[s[i]]=t[i];
                m2[t[i]]=s[i];
            }else if(m[s[i]]!=t[i]||m2[t[i]]!=s[i]){
                return false;
            }
        }
        return true;
    }
};

Isomorphic Strings

原文：http://blog.csdn.net/u010786672/article/details/45399507