ElementaryMathExamples-mscarries01

test for : mscarries crossout='downdiagonalstrike'

W3C sample	WIRIS
	$212\mathrm{2,327}-\mathrm{1,156}\mathrm{1,171}$

<math xmlns="http://www.w3.org/1998/Math/MathML">
  <mstack>
    <mscarries crossout="downdiagonalstrike">
      <mn>2</mn>
      <mn>12</mn>
      <mscarry crossout="none">
        <none/>
      </mscarry>
    </mscarries>
    <mn>2,327</mn>
    <msrow>
      <mo>-</mo>
      <mn>1,156</mn>
    </msrow>
    <msline/>
    <mn>1,171</mn>
  </mstack>
</math>

Author: Yecheng Gu