<p>filter 사용하지 않고 아래와 같이 indexOf만 이용해도 될까요?&nbsp;</p>
<p>&nbsp;</p>
<div style="color: #d4d4d4; background-color: #1e1e1e; font-family: Menlo, Monaco, 'Courier New', monospace; font-size: 12px; line-height: 18px; white-space: pre;">
<div><span style="color: #569cd6;">function</span> <span style="color: #dcdcaa;">solution</span>(<span style="color: #9cdcfe;">str</span>) {</div>
<div><span style="color: #569cd6;">let</span> <span style="color: #9cdcfe;">answer</span> = <span style="color: #ce9178;">""</span>;</div>
<br />
<div><span style="color: #c586c0;">for</span> (<span style="color: #569cd6;">let</span> <span style="color: #9cdcfe;">i</span> = <span style="color: #b5cea8;">0</span>; <span style="color: #9cdcfe;">i</span> &lt; <span style="color: #9cdcfe;">str</span>.<span style="color: #9cdcfe;">length</span>; <span style="color: #9cdcfe;">i</span>++) {</div>
<div><span style="color: #9cdcfe;">console</span>.<span style="color: #dcdcaa;">log</span>(<span style="color: #9cdcfe;">str</span>[<span style="color: #9cdcfe;">i</span>], <span style="color: #9cdcfe;">i</span>, <span style="color: #9cdcfe;">str</span>.<span style="color: #dcdcaa;">indexOf</span>(<span style="color: #9cdcfe;">str</span>[<span style="color: #9cdcfe;">i</span>]));</div>
<div><span style="color: #c586c0;">if</span> (<span style="color: #9cdcfe;">str</span>.<span style="color: #dcdcaa;">indexOf</span>(<span style="color: #9cdcfe;">str</span>[<span style="color: #9cdcfe;">i</span>]) === <span style="color: #9cdcfe;">i</span>) <span style="color: #9cdcfe;">answer</span> += <span style="color: #9cdcfe;">str</span>[<span style="color: #9cdcfe;">i</span>] + <span style="color: #ce9178;">" "</span>;</div>
<div>}</div>
<div><span style="color: #c586c0;">return</span> <span style="color: #9cdcfe;">answer</span>;</div>
<div>}</div>
</div>

<p>안녕하세요^^</p>
<p>네. 상관없습니다.</p>

인프런 커뮤니티 질문&답변

답변 부탁드립니다!