Adiff ← 180 - 360 | 180 + -

tests ← [20‿45, ¯45‿45, ¯85‿90, ¯95‿90, ¯45‿125, ¯45‿145
         99‿279, 29.4803‿¯88.6381, ¯78.3251‿¯159.036
         ¯70099.74233810938‿29840.67437876723
         ¯165313.6666297357‿33693.9894517456
         1174.8380510598456‿¯154146.66490124757
         60175.77306795546‿42213.07192354373]

Round ← ⌊∘+⟜0.5⌾(1e3⊸×)

Round∘∾⟜(Adiff´)˘ tests