jQuery验证器不适用于我的多输入

Question

我需要jquery验证程序来帮助我检查已填充的输入。验证器出现问题。 验证程序仅工作并检查第一部分，第二部分将无法正确检查

<h1>Form Validation Example</h1>
<form id="registerForm">
<p>
  firstname: <input type='text' name='firstname[]' id='firstname' />
</p>
<p>
  lastname: <input type='text' name='lastname[]' id='lastname' />
</p>
mobile: <input type='text' name='mobile[]' id='mobile' />
<p>
  ic: <input type='text' name='ic[]' id='ic' />
</p>
<br>
<hr>
<p>
  firstname: <input type='text' name='firstname[]' id='firstname' />
</p>
<p>
  lastname: <input type='text' name='lastname[]' id='lastname' />
</p>
<p>
  mobile: <input type='text' name='mobile[]' id='mobile' />
</p>
<p>
  ic: <input type='text' name='ic[]' id='ic' />
</p>
<br>
<hr>
<p>
  firstname: <input type='text' name='firstname[]' id='firstname' />
</p>
<p>
  lastname: <input type='text' name='lastname[]' id='lastname' />
</p>
<p>
  mobile: <input type='text' name='mobile[]' id='mobile' />
</p>
<p>
  ic: <input type='text' name='ic[]' id='ic' />
</p>
<p>
  <input type='submit' name='Submit' value='Submit' />
</p>
</form>

$(document).ready(function() {
  $("#registerForm").validate({
    rules: {
      'firstname[]': {
        required: true,
        minlength: 1
      },
      'lastname[]': {
        required: true,
        minlength: 1
      },
      'mobile[]': {
        required: true,
        minlength: 1
      },
      'ic[]': {
        required: true,
        minlength: 1
      },
    },
    messages: {
      "firstname[]": {
        required: 'no firstname'
      },
      "lastname[]": {
        required: 'no lastname'
      },
      "mobile[]": {
        required: 'no mobile'
      },
      "ic[]": {
        required: 'no ic'
      },
    },
  });
});

我需要jquery验证器来检查所有填充的输入 如果姓氏已填写，则姓氏mobile_no && ic不能为空/空。除非名字为空，否则其余的可以为空