forward and reverse loop one by one js

var arr = [‘red’, ‘blue’, ‘black’, ‘green’];<br /> var currentIndex = 0;</p> <p>var nextBtn = document.getElementById(‘nextBtn’);<br /> var prevBtn = document.getElementById(‘prevBtn’);</p> <p>nextBtn.addEventListener(‘click’, nextItem);</p> <p>prevBtn.addEventListener(‘click’, prevItem);</p> <p>function nextItem() {<br /> if (currentIndex === (arr.length – 1)) {<br /> return;<br /> }</p> <p> console.log(<br /> arr[++currentIndex]<br /> );<br /> }</p> <p>function prevItem() {<br /> if (currentIndex === 0) {<br /> return;<br /> }</p> <p> console.log(<br /> arr[–currentIndex]<br /> );<br /> }