find the longest sorted sequence in javascript

index.tsx
function longestSortedSequence(arr) {
  let longestSeqLength = 1;
  let currentSeqLength = 1;
  let longestSeqStartIndex = 0;
  let currentSeqStartIndex = 0;

  for (let i = 1; i < arr.length; i++) {
    if (arr[i] >= arr[i-1]) {
      // current element is part of the sorted sequence
      currentSeqLength++;
    } else {
      // current element is not part of the sorted sequence
      if (currentSeqLength > longestSeqLength) {
        longestSeqLength = currentSeqLength;
        longestSeqStartIndex = currentSeqStartIndex;
      }
      currentSeqLength = 1;
      currentSeqStartIndex = i;
    }
  }

  // handle the case where the longest sorted sequence is at the end of the array
  if (currentSeqLength > longestSeqLength) {
    longestSeqLength = currentSeqLength;
    longestSeqStartIndex = currentSeqStartIndex;
  }

  return arr.slice(longestSeqStartIndex, longestSeqStartIndex + longestSeqLength);
}
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index.tsx
const arr = [1, 2, 3, 1, 2, 3, 4, 5, 4, 3, 2, 1, 2, 3, 4];
const longestSeq = longestSortedSequence(arr);
console.log(longestSeq); // [1, 2, 3, 4, 5]
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