[Leetcode] 1768.Merge Strings Alternately

 

Merge Strings Alternately - LeetCode

You are given two strings word1 and word2. Merge the strings by adding letters in alternating order, starting with word1. If a string is longer than the other, append the additional letters onto the end of the merged string.
Return the merged string.

 

나의 풀이

const mergeAlternately = function (word1, word2) {
    const totalLength = Math.max(word1.length, word2.length)
    const result = [];

    for(let i = 0; i < totalLength; i++) {
        result.push(word1[i])
        result.push(word2[i])
    }

    return result.join('')
};

 

• join 메서드를 사용하면 배열 값이 null 이거나 undefined 인 경우 빈 문자열로 치환됨
• 즉 없어짐

추가된 풀이

var mergeAlternately = function(word1, word2) {
    let result = '';

    for(let i = 0; i < Math.max(word1.length, word2.length); i++) {
        result += word1[i] ?? '';
        result += word2[i] ?? '';
    }

    return result;
};

• nullish 연산자를 사용해서 빈 문자열을 더해버림