https://leetcode.com/problems/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.
class Solution { public: bool isIsomorphic(string s, string t) { if(s.empty() && t.empty()) return true; if(s.length() != t.length()) return false; map<char, char> s_t_hsh; s_t_hsh.clear(); map<char, char> t_s_hsh; t_s_hsh.clear(); map<char, char>::iterator p_s_t, p_t_s; for(int i=0;i<s.length();++i) { p_s_t = s_t_hsh.find(s[i]); p_t_s = t_s_hsh.find(t[i]); if(p_s_t != s_t_hsh.end() && p_s_t->second != t[i]) return false; else s_t_hsh.insert(pair<char,char> (s[i],t[i])); if(p_t_s != t_s_hsh.end() && p_t_s->second != s[i]) return false; else t_s_hsh.insert(pair<char,char> (t[i],s[i])); } return true; } };
leetcode@ [205] Isomorphic Strings
原文：http://www.cnblogs.com/fu11211129/p/5013339.html
