Broken sequence.js

// You receive some random elements as a space-delimited string. Check if the elements are part of an ascending sequence of integers starting with 1, with an increment of 1 (e.g. 1, 2, 3, 4).

// Return:

// 0 if the elements can form such a sequence, and no number is missing ("not broken", e.g. "1 2 4 3")
// 1 if there are any non-numeric elements in the input ("invalid", e.g. "1 2 a")
// n if the elements are part of such a sequence, but some numbers are missing, and n is the lowest of them ("broken", e.g. "1 2 4" or "1 5")
// Examples
// "1 2 3 4"  ==>  return 0, because the sequence is complete

// "1 2 4 3"  ==>  return 0, because the sequence is complete (order doesn't matter)

// "2 1 3 a"  ==>  return 1, because it contains a non numerical character

// "1 3 2 5"  ==>  return 4, because 4 is missing from the sequence

// "1 5"      ==>  return 2, because the sequence is missing 2


function findMissingNumber(sequence){
    //your code 
    if (sequence.trim() === '') {
      return 0; // Empty sequence
    }
  
    const elements = sequence.split(' ');
    const sortedElements = elements.filter(el => !isNaN(el)).sort((a, b) => a - b);
  
    if (elements.some(el => isNaN(el))) {
      return 1; // Contains non-numeric elements
    }
  
    for (let i = 0; i < sortedElements.length; i++) {
      const num = parseInt(sortedElements[i]);
      if (num !== i + 1) {
        return i + 1; // Missing number found
      }
    }
  
    return 0; // Sequence is complete
  }