<pre><code class="language-javascript">
/**
 * @param { Array } arr
 * @param { number } depth
 * @returns { Array }
 */
function flat(arr, depth = 1) {
  // your imeplementation here
  
  var recursive = (arr, depth)=&gt;{
      if(depth === 0) {
        return arr
      }
      let res = []
      for(let i=0; i &lt; arr.length; i++){
        if(Array.isArray(arr[i])){ 
          res.push(...recursive(arr[i], depth-1))
        }
        else{
          res.push(arr[i])
        }
      }
      return res
  }
  return recursive(arr, depth)
}
</code></pre>


This is my accepted solution

There is already Array.prototype.flat() in JavaScript (ES2019), which reduces the nesting of Array. Could you manage to implement your own one? Here i…

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