205. Isomorphic Strings 字符串相似
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.
題目大意：
判斷兩個字符串是否相似。
思路：
使用雙map來進行比較。map鍵爲字符串元素，值爲字符上一次出現的位置。
代碼如下：
class Solution {
public:
bool isIsomorphic(string s, string t) {
if(s.size() != t.size())
return false;
unordered_map<char,int> maps;
unordered_map<char,int> mapt;
for(int i = 0;i < s.size();i++)
{
if(maps.find(s[i]) == maps.end() && mapt.find(t[i]) == mapt.end())
{
maps.insert(pair<char,int>(s[i],i));
mapt.insert(pair<char,int>(t[i],i));
}
else if(maps.find(s[i]) != maps.end() && mapt.find(t[i]) != mapt.end())
{
if(maps[s[i]] != mapt[t[i]])
return false;
else
{
maps[s[i]] = i;
mapt[t[i]] = i;
}
}
else
return false;
}
return true;
}
};2016-08-13 17:15:21