<?php
/*
* bcadd = adição
* bcsub = subtração
* bcmul = multiplicação
* bcdiv = divisão
*/
$operador = 'add';
$val1 = 10;
$val2 = 10;
echo $result;
PD9waHAKLyoKICogYmNhZGQgPSBhZGnDp8OjbwogKiBiY3N1YiA9IHN1YnRyYcOnw6NvCiAqIGJjbXVsID0gbXVsdGlwbGljYcOnw6NvCiAqIGJjZGl2ID0gZGl2aXPDo28KICovCiRvcGVyYWRvciA9ICdhZGQnOwokdmFsMSA9IDEwOwokdmFsMiA9IDEwOwokcmVzdWx0ID0gY2FsbF91c2VyX2Z1bmMoJ2JjJy4kb3BlcmFkb3IsJHZhbDEsJHZhbDIpOwplY2hvICRyZXN1bHQ7