[Leet Code] Word Pattern

Leet Code: https://leetcode.com/problems/word-pattern/

Problem:

Given a pattern and a string s, find if s follows the same pattern.

Here follow means a full match, such that there is a bijection between a letter in pattern and a non-empty word in s.

Example 1:

Input: pattern = "abba", s = "dog cat cat dog"
Output: true

Example 2:

Input: pattern = "abba", s = "dog cat cat fish"
Output: false

Example 3:

Input: pattern = "aaaa", s = "dog cat cat dog"
Output: false

Example 4:

Input: pattern = "abba", s = "dog dog dog dog"
Output: false

Constraints:

• 1 <= pattern.length <= 300
• pattern contains only lower-case English letters.
• 1 <= s.length <= 3000
• s contains only lower-case English letters and spaces ' '.
• s does not contain any leading or trailing spaces.
• All the words in s are separated by a single space.

Solution:

class Solution(object):
    def wordPattern(self, pattern, s):
        """
        :type pattern: str
        :type s: str
        :rtype: bool
        """
        s_list = []
        pattern_list = []
        s_current = ""
        pattern_current = ""
        s_count = 0
        pattern_count = 0
        
        previous_answers_s = {}
        previous_answers_pattern = {}
        
        for i in s.split(" "):
            if i not in previous_answers_s:
                s_count += 1
                previous_answers_s[i] = s_count
                s_list.append(s_count)
                s_current = i
            else:
                s_list.append(previous_answers_s[i])
        for i in pattern:
            if i not in previous_answers_pattern:
                
                pattern_count += 1
                previous_answers_pattern[i] = pattern_count
                pattern_list.append(pattern_count)
                pattern_current = i
            else:
                pattern_list.append(previous_answers_pattern[i])
        if str(pattern_list) == str(s_list):
            return True
        else:
            return False