# Validate Subsequences

<figure><img src="https://3743232000-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FHW2IQuh2PFpWJDvBz2FF%2Fuploads%2Fgit-blob-3ac6425445e18b23a969b3eb1c4a304549afdc72%2FScreenshot%202023-01-20%20at%2015.00.16.png?alt=media" alt=""><figcaption></figcaption></figure>

```javascript
function isValidSubsequence(arr, sequence) {
  let idx = 0;
  let seq = 0;
  
  while (seq < sequence.length && idx < arr.length) {
    const curr = sequence[seq];

    if (curr === arr[idx]) {
      seq++;
    }
    
    idx++;
  }

  if (sequence.length !== seq) {
    return false;
  }

  return true;
}

// Do not edit the line below.
exports.isValidSubsequence = isValidSubsequence;
```