we-NX
ys-px
ys-we
px-end
yq-NX
px-NX
yq-px
qk-yq
pr-NX
wq-EY
pr-oe
wq-pr
ys-end
start-we
ys-start
oe-DW
EY-oe
end-oe
pr-yq
pr-we
wq-start
oe-NX
yq-EY
ys-wq
ys-pr