leetcode_c++：哈希：Isomorphic Strings(205)

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.
// 判断两个字符是否可以直接映射

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算法

o(n)

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class Solution {public:    bool isIsomorphic(string s, string t) {        if(s.size()!=t.size())  return false;        const int MAXCHAR = 256;        char maps[MAXCHAR]={0}, mapt[MAXCHAR]={0};        for(int i=0;i<s.size();i++){            if(maps[s[i]]==0 && mapt[t[i]]==0){                maps[s[i]]=t[i];                mapt[t[i]]=s[i];                continue;            }            if(maps[s[i]]==t[i] && mapt[t[i]]==s[i])                continue;            return false;        }        return true;    }};