def add$\_$fp$\_$bin$($u$,$ v$,$ signif$\_$bits$)$:

u$\_$sign, u$\_$signif, u$\_$exp $=$ u

v$\_$sign, v$\_$signif, v$\_$exp $=$ v

# You may assume normalized inputs at the given precision, $`$signif$\_$bits$`.$

assert u$\_$signif$[$:$2]$ in $\{\text{'}1.\text{'},\text{'}0.\text{'}\}$ and len$($u$\_$signif$)==($signif$\_$bits$+1)$

assert v$\_$signif$[$:$2]$ in $\{\text{'}1.\text{'},\text{'}0.\text{'}\}$ and len$($v$\_$signif$)==($signif$\_$bits$+1)$