LeetCode题解：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.

题意：字符串S和T的组成字符只能单对单映射，而且两个字符串内互相映射的字符出现位置必须一致

解决思路：用两个大小为256的数组存储字符串内字符对应的映射关系

代码：

public class Solution {
    public boolean isIsomorphic(String s, String t) {
        int[] sChars = new int[256];
        int[] tChars = new int[256];

        for(int i = 0;i < s.length();++i){
            if(sChars[s.charAt(i)] != tChars[t.charAt(i)]){
                return false;
            }else{
                sChars[s.charAt(i)] = tChars[t.charAt(i)] = t.charAt(i);
            }
        }

        return true;
    }
}