input: [2] whether to position on least upper bound or greatest lower bound [1] 
output: leastUpper
options: k e y
options: d u p S e e k
options: l e a s t U p p e r
options: p a g e S t a c k
options: s t a r t P a g e I d
options: i n i t i a l L o c k M o d e
options: r e a d M o d e