1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 | language Essence 1.3 $ prob006.essence: Golomb Ruler Problem $ Problem details available at http://www.csplib.org/Problems/prob006/ $ $ Given n, put n integer ticks on a ruler of size m so that all inter-tick $ distances are unique. Minimise m, $ $ 03 September 2007 $ given n : int (1..) letting bound be 2 ** n find Ticks : set ( size n) of int (0..bound) minimising max (Ticks) such that $ implied 0 in Ticks, forAll {i, j} subsetEq Ticks . forAll {k, l} subsetEq Ticks . {i, j} != {k, l} -> i - j != k - l |