Pattern Matching

[BennettElisa]

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Category of the bug :

• [ ] Question
• [X] Solution
• [ ] Language

Description of the bug :

Code you used for Submit/Run operation :

const findAndReplacePattern = (words, pattern) => {

    // create array literal to return matching patterns
    const results = []

    // iterate over the array of words 
    for(let i =0; i< words.length; i++){
        // edge case if the length doesn't match skip it. 
        if(words[i].length != pattern.length){
            continue;
        }
        // if the word matches the pattern push into results
       // Use isMatch function break words down by characters and compare to pattern
        if(isMatch(words[i], pattern)){
            results.push(words[i])
        }
    }

    // return array with patterns that match or empty array if no matches are found
    return results;

}

// Determine if pattern matches word
const isMatch = (word, pattern) => {

    // create data structure to store key value pairs to map pattern char to word char
    const hash = new Map()
    // iterate over the word (string) and look at each character
    for(let i = 0; i < word.length; i++){
        // if the letter from the pattern doesn't exist add to hash map
        if(!hash.has(pattern[i])){
            // set the key value pair for the mapping
            hash.set(pattern[i], word[i])
        }
        // if the pattern char does exist, make sure it matches the word char it was originally mapped to - if not - return false 
        if(hash.get(pattern[i]) != word[i]){
            return false 
        }
    }

    // if we break out of the loop we know it was a match and can return true 
    return true

}

Language used for code :

JavaScript

Expected behavior :

Screenshots :

Additional context :