Data commit

Task/Successive-prime-differences/Prolog/successive-prime-differences.pro

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+prime(2).     % use swi prolog
+prime(N):-
+	N /\ 1 > 0,              % odd
+	M is floor(sqrt(N)) - 1, % reverse 2*I+1
+	Max is M // 2,           % integer division
+	forall(between(1, Max, I), N mod (2*I+1) > 0).
+
+primesByDiffs([],_,[]).
+primesByDiffs([Prime|Primes], Diff, [Slide|Slides]):-
+	length(Diff, Len0),
+	Len is Len0 + 1,
+	length(Slide, Len),
+	append(Slide, _, [Prime|Primes]),
+	select(Diff, Slide),!,
+	primesByDiffs(Primes, Diff, Slides).
+primesByDiffs([_|Primes], Diff, Slides):-
+	primesByDiffs(Primes, Diff, Slides).
+
+select([],_).
+select([Diff|Diffs],[S1, S2|Stail]):-
+	S2 is S1 + Diff,
+	select(Diffs, [S2|Stail]).
+
+run([],_).
+run([Diff|Dtail], PrimeList):-
+	statistics(runtime,[Start|_]),
+	primesByDiffs(PrimeList, Diff, SlideList),	
+	length(SlideList, Num),
+	statistics(runtime,[Stop|_]),
+	Runtime is Stop - Start,
+	SlideList = [First|SlideTail],
+	format('~|~w~t~7+ number: ~|~t~d~4+ [time(ms) ~|~t~d~3+] first: ~|~w~t~22+',[Diff, Num, Runtime, First]),
+	writeLast(SlideTail),!, nl,
+	run(Dtail, PrimeList).
+
+writeLast([]).
+writeLast(SlideTail):-
+	last(SlideTail, Last),
+	format('last: ~w',[Last]).
+
+do:-	Num is 1000000,
+	statistics(runtime,[Start|_]),
+	numlist(2, Num, List),
+	include(prime, List, PrimeList),
+	length(PrimeList, NumPrimes),
+	statistics(runtime,[Stop|_]),
+	RunTime is Stop - Start,
+	format('there are ~w primes until ~w [time(ms) ~w]~n',[NumPrimes, Num, RunTime]),
+	DiffList = [[1], [2], [2,2], [2,4], [4,2], [2,4,6],
+		    [2,6,4], [4,2,6], [4,6,2], [6,2,4], [6,4,2]],
+	run(DiffList, PrimeList).