205.isomorphic-strings

Statement

简体中文English

Metadata

• Link: 同构字符串
• Difficulty: Easy
• Tag: 哈希表 字符串

给定两个字符串 s 和 t ，判断它们是否是同构的。

如果 s 中的字符可以按某种映射关系替换得到 t ，那么这两个字符串是同构的。

每个出现的字符都应当映射到另一个字符，同时不改变字符的顺序。不同字符不能映射到同一个字符上，相同字符只能映射到同一个字符上，字符可以映射到自己本身。

 

示例 1:

输入：s = "egg", t = "add"
输出：true

示例 2：

输入：s = "foo", t = "bar"
输出：false

示例 3：

输入：s = "paper", t = "title"
输出：true

 

提示：

• 1 <= s.length <= 5 * 104
• t.length == s.length
• s 和 t 由任意有效的 ASCII 字符组成

Metadata

• Link: Isomorphic Strings
• Difficulty: Easy
• Tag: Hash Table String

Given two strings s and t, determine if they are isomorphic.

Two strings s and t 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.

 

Example 1:

Input: s = "egg", t = "add"
Output: true

Example 2:

Input: s = "foo", t = "bar"
Output: false

Example 3:

Input: s = "paper", t = "title"
Output: true

 

Constraints:

• 1 <= s.length <= 5 * 104
• t.length == s.length
• s and t consist of any valid ascii character.

Solution

Python 3

class Solution:
    def isIsomorphic(self, s: str, t: str) -> bool:
        sd = {}
        st = {}
        for i in range(len(s)):
            try:
                if sd[s[i]] != t[i]:
                    return False
            except KeyError:
                sd[s[i]] = t[i]

            try:
                if st[t[i]] != s[i]:
                    return False
            except KeyError:
                st[t[i]] = s[i]

        return True

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最后更新: October 11, 2023