function z_:construct

function z_:stdin { v: 1 }

$scoreboard players operation _reg_a _mcfstd_reg = $(a) _mcfstd_var

$scoreboard players operation _reg_a _mcfstd_reg -= $(b) _mcfstd_var

execute unless score _reg_a _mcfstd_reg matches 0 run return fail

function z_:stdin { v: 0 }