要求从1开始,最终回到1,且路径有方向,要求所有路径都经过。 & }8 v* k9 A. l' S8 ~9 m
以下是lingo的代码( }" k$ [; m$ V# O
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nodes/A,B,C,D,E,F,G,H,I,J,K,L/;
, B& C# Z$ z1 B6 C( ^arcs(nodes,nodes)/
$ l% o) U6 p. f0 Q. @! V3 [& XA,B A,E
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C,B C,D% i: a3 N. R1 _8 E/ ?) D2 t
D,C D,H
: W0 v" z) ]; aE,A E,F
& q) T$ I* _# ]$ FF,B F,E F,G F,I F,J
1 ~6 `0 ~, [5 y# ~$ rG,C G,F G,H G,K
C* y5 b! U. K7 z/ Q# r5 g" \, mH,D H,K H,L+ T) W7 v7 R% u2 G1 p
I,E I,J6 l6 H# L, a* ]3 u
J,F J,G( ~0 o, q( A, y, N* R% f$ f* B
K,G K,J' p4 U$ X& n' ~+ D' s. n
L,K
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4 P# _) w; r/ R& D/ r6 X- eendsets
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150 165
, Z& k3 ~) N) w1 Z% A3 ^; r130 230 160) o9 H' D% C$ ^2 p
140 100
! q% ~7 @# k( X100 190
: x j. B0 R. \2 g/ }165 144
% t( l; H1 {; y; `. W, `/ R/ x* K9 ^- l6 b170 144 128 218 1747 E" P+ ?/ s! C+ V$ V
200 122 109 185 z6 ^9 o) X6 }
180 141 190% B+ N$ ` q* o5 Q; }
194 148
0 c0 l$ s9 o9 ]: f; {, l174 233
% p5 C: Y* q1 g ^/ k5 L$ C185 135
$ a% o2 v8 t2 h& B2 P, @110;
4 T# b6 W s. E9 Jenddata
8 Z' N% _" U' O+ ~5 k$ P5 ln = @size(nodes);
4 N+ }1 r- U+ r/ Gmin = @sum(arcs: c * x);
( H1 r4 S+ t* _5 m' t2 L@for(nodes(i):
" l- F& o# P- N8 e4 M+ M2 Z- E# U@sum(arcs(i,j):x(i,j))=@sum(arcs(k,i):x(k,i))
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& C0 \ f7 N2 }* ~8 j: A& @2 F7 i, H@for(arcs: @bnd(1,x,9));
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$ C) _ [9 S& b: S( _它只能算出路径的步数和路程,并不能得到线路。希望能用mma解决这个问题。 --------------------------------------------------------------------- 自己用mma写的程序对于四点还可以,但是扩展到12点实在繁琐: ) o0 L! c) x- o! ^. j! V3 q
P11 = {2, 5}; P12 = {150, 165}; P21 = {5, 6}; P22 = {230, 160}; P51 = {1, 6}; P52 = {165, 144}; P61 = {2, 5}; P62 = {170, 144};(*只考虑1、2、5、6四点,P11为第一点“可去往的点”,P12表述对应的路程*) open[q_] := Module[{i = 1, randomD, randomP, D, randomreal, p1, p2, p5, p6, c, u, Df = 80000, uf, path = {1}, pathf = {1}, pb},(*随机搜索*) For[r = 0, r < q, r++, {p1 = {}; p2 = {}; p5 = {}; p6 = {}; u = 0; D = 0; i = 1; randomP = P11; randomD = P12; While[ Length[p1] != 2 || Length[p2] != 2 || Length[p5] != 2 || Length[p6] != 2 || i != 1, randomreal = RandomInteger[{1, Length[randomP]}]; c = randomP[[randomreal]]; AppendTo[path, c];(*Print[path];*) Which[ i == 1 && Product[If[p1[] != c, 1, 0], {i, 1, Length[p1]}] == 1, {AppendTo[p1, c]}, i == 2 && Product[If[p2[] != c, 1, 0], {i, 1, Length[p2]}] == 1, {AppendTo[p2, c]}, i == 5 && Product[If[p5[] != c, 1, 0], {i, 1, Length[p5]}] == 1, {AppendTo[p5, c]}, i == 6 && Product[If[p6[] != c, 1, 0], {i, 1, Length[p6]}] == 1, {AppendTo[p6, c]}]; i = c; D = D + randomD[[randomreal]]; Which[i == 1, {randomP = P11, randomD = P12}, i == 2, {randomP = P21, randomD = P22}, i == 5, {randomP = P51, randomD = P52}, i == 6, {randomP = P61, randomD = P62}]; u = u + 1; If[u > 11, Break[]]; If[Df > D, {Df = D, uf = u, pathf = path, path = {1}}, path = {1}]; } ]; Print[Df, ",", uf, ",", pathf]; ' b% w- V8 N Z' U/ H" ~' |
open[1000] " Y7 i6 L* C7 I3 ]6 L, A
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