What is the task performed by the following algorithm?

A: a bit vector $($an array storing only $1\text{'}$s and $0\text{'}$s$)$

pos: highest index of array $A$

function $,$ pos $)$

if $(pos<mi\; id="EditorElement\_956316"></mi><mi\; id="EditorElement\_956318">)</mi>$

return $$

if $($pos$0$ or pos$-1]==1$ or $A[pos+1]==1)$

return $,$ pos $-1$