<pre class="shiki github-dark shaku"><code>/** * @param {string} str * @returns {string} */function uncompress(s) {let stack = []; let num = 0; for (let i = 0; i &lt; s.length; i++) { let char = s[i]; if (!isNaN(char)) { num = num * 10 + parseInt(char); } else if (char === '(') { stack.push(num); num = 0; stack.push(char); } else if (char === ')') { let substr = ''; while (stack.length &amp;&amp; stack[stack.length - 1] !== '(') { substr = stack.pop() + substr; } stack.pop(); // remove '(' let repeatTimes = stack.pop(); stack.push(substr.repeat(repeatTimes)); } else { stack.push(char); } } return stack.join('');}console.log(uncompress('1(BFE11(dev))'))</code></pre>

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Given a compressed string, return its original form. For example. uncompress('3(ab)') // 'ababab'uncompress('3(ab2(c))') // 'abccabccabcc' 1. a number…