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

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