How to determine the size of the version number

How to determine the size of the version number

<script>
    function compareVersion(source, target) {
    
      if (typeof source !== 'string' || typeof target !== 'string') return 'The parameter passed in needs to be in the form of a string'
      const sourceArr = source.split('.');
      const targetArr = target.split('.');
      for (let index = 0; index < sourceArr?.length; index++) {
    
        if (sourceArr[index] !== targetArr[index]) {
    
          if (sourceArr[index] > targetArr[index]) {
    
            return 1
          }
          return -1
        }
      }
    }
    const a = compareVersion('1.0.3', '1.0.5');
    console.log(a, 'a is');
    const b = compareVersion('1.0.7', '1.0.5');
    console.log(b)
</script>