$4890 \overset{1}{+} 346 \overset{2}{+} 15678 = 20914$
1)
$\snippet{name: op_column, sign: '+', x: '4890', y: '346', z: '5236 '}$
2)
$\snippet{name: op_column, sign: '+', x: '5236', y: '15678', z: '20914 '}$

81315 − 9637 = 71678
$\snippet{name: op_column, sign: '-', x: '81315', y: '9637', z: '71678 '}$