标签：
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.
看两个字符串是否同构,用map就可以解决，不过要注意双向都要检查，代码如下：
1 class Solution { 2 public: 3 bool isIsomorphic(string s, string t) { 4 map<char, char> m1; 5 map<char, char> m2; 6 if(s.size() != t.size()) 7 return false; 8 for(int i = 0; i < s.size(); ++i){ 9 if(m1.find(s[i]) == m1.end() && m2.find(t[i]) == m2.end()){ 10 m1[s[i]] = t[i]; 11 m2[t[i]] = s[i]; 12 } 13 else if(m1.find(s[i]) != m1.end() && m2.find(t[i]) != m2.end()){ 14 if(m1[s[i]] != t[i] || m2[t[i]] != s[i]) 15 return false; 16 }else{ 17 return false; 18 } 19 } 20 return true; 21 } 22 };
LeetCode OJ：Isomorphic Strings（同构字符串）
标签：
原文地址：http://www.cnblogs.com/-wang-cheng/p/4987700.html
