Railway circuit: Difference between revisions

Count the number of circuits   '''Cn,m'''   with   '''n'''   same as above and   '''m''' = 2  to  8

<br><br>

 

=={{header|EchoLisp}}==

;; R is turn counter in right direction

;; The nb of right turns in direction i

(printf "Number of circuits C%d,%d : %d" maxn straight (vector-length *circuits*)))

(when (< (vector-length *circuits*) 20) (for-each writeln *circuits*)))

{{out}}

<pre>

=={{header|Go}}==

{{trans|Kotlin}}

 

import "fmt"

}

circuits(12, 4)

 

{{out}}

1 1 1 0 1 1 1 0 1 1 1 0 1 1 1 0

</pre>

 

=={{header|Java}}==

{{works with|Java|8}}

 

import static java.util.Arrays.stream;

return carry != 1;

}

<pre>1 solution(s) for C12,0

1 1 1 1 1 1 1 1 1 1 1 1

 

=={{header|Julia}}==

same point faciing in the same direction. Track are either right handed or left handed 30 degree

curves or are straight track that can be placed at -90, 0, or 90 degree angles from starting points.

So, the equivalence group is composed: (rotational permutations) X (scalar multiplication by -1)

 

 

Furthermore, if chosen, reversal of the turns vector (not mentioned as a source of symmetry in the task)

 

Graphic displays of solutions are via a Gtk app and Cairo graphics.

""" Rosetta Code task rosettacode.org/wiki/Railway_circuit. """

 

end

 

for i = 4:2:36, rev in false:true, str in false:true

str && i > 16 && continue

@time allvalidcircuits(i; verbose = !str && i < 28, reversals = rev, straight = str, graphic = i == 24)

end

<pre>

For N of 4 and curved track, including reversed curves:

588.433178 seconds (2.16 G allocations: 610.226 GiB, 19.45% gc time)

 

Found 2793 unique valid circuits.

1010.080701 seconds (8.84 G allocations: 2.703 TiB, 14.50% gc time)

1333.508776 seconds (8.73 G allocations: 2.669 TiB, 16.66% gc time)

 

 

For N of 34 and curved track, excluding reversed curves:

Found 3975 unique valid circuits.

5092.741859 seconds (35.46 G allocations: 10.836 TiB, 18.86% gc time, 0.00% compilation time)

</pre>

 

{{trans|Java}}

It takes several minutes to get up to n = 32. I called it a day after that!

 

const val RIGHT = 1

for (n in 12..32 step 4) circuits(n, 0)

circuits(12, 4)

 

{{out}}

It took about 2 min 25 s to get the result for a maximum of 32 and 41 min 15 s for a maximum of 36.

 

 

type

for n in countup(12, 36, 4):

circuits(n, 0)

 

{{out}}

{{trans|Raku}}

{{libheader|ntheory}}

use warnings;

use feature 'say';

 

allvalidcircuits($_, True) for 12, 16, 20;

{{out}}

<pre>For N of 12 and curved track:

=={{header|Phix}}==

{{trans|Go}}

<span style="color: #008080;">with</span> <span style="color: #008080;">javascript_semantics</span>

<span style="color: #008080;">constant</span> <span style="color: #000000;">right</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span><span style="color: #0000FF;">,</span>

<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>

<span style="color: #000000;">circuits</span><span style="color: #0000FF;">(</span><span style="color: #000000;">12</span><span style="color: #0000FF;">,</span><span style="color: #000000;">4</span><span style="color: #0000FF;">)</span>

{{out}}

<pre>

 

=={{header|Python}}==

import numpy as np

from numpy import sin, cos, pi

sols.append(s)

 

 

=={{header|Racket}}==

Made functional, so builds the track up with lists. A bit more expense spent copying vectors, but this solution avoids mutation (except internally in <code>vector+=</code> . Also got rid of the maximum workload counter.

 

 

(define-syntax-rule (vector+= v idx i)

(gen 20)

(gen 24)

 

{{out}}

 

{{trans|Julia}}

 

# 20200406 Raku programming solution

 

allvalidcircuits($_, $_ < 28) for 12, 16, 20; # 12, 16 … 36

{{out}}

<pre>For N of 12 and curved track:

{{trans|Kotlin}}

 

case left = -1, straight, right

}

}

 

 

{{out}}

 

=={{header|Wren}}==

{{libheader|Wren-math}}

 

 

 

}

}

 

 

 

}

 

}

}

 

}

}

}

}

 

}

}

}

 

}

}

 

 

{{out}}

<pre>

 

 

 

 

 

</pre>

 

=={{header|zkl}}==

{{trans|EchoLisp}}

// The nb of right turns in direction i

// must be = to nb of right turns in direction i+6 (opposite)

else println("Number of circuits C%,d,%d : %d".fmt(maxn,straight,_circuits.len()));

if(_circuits.len()<20) _circuits.apply2(T(T("toString",*),"println"));

gen(16); println();

gen(20); println();

gen(24); println();

{{out}}

<pre>