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(l, r) defines a line whose left end is at l and the right end is at r, on a 1-dimensional space.
Given 2 lines b = (0, bz) and f = (i, i + fz), v = (l, r) is the overlapping part of these lines. When b and f do not overlap, v = (0, 0).
(input) -> (output)
bz, fz, i -> l, r
The data type for e...