本帖最后由 王守恩 于 2019-11-16 13:26 编辑
在五座岛屿之间建造四座桥,使它们能够联通,请问有几种建桥方案?
共有125种建桥方案。
先固定3座桥(等号左边),
再选第4座桥的建桥方案(等号右边)。
04:12,13,14=15,25,35,45
07:12,13,15=24,34,45
07:12,13,23=0
10:12,13,24=25,35,45
12:12,13,25=34,45
14:12,13,34=35,45
15:12,13,35=45
18:12,14,15=23,34,35
21:12,14,23=25,35,45
21:12,14,24=0
23:12,14,25=34,35
25:12,14,34=35,45
26:12,14,35=45
29:12,15,23=24,34,45
31:12,15,24=34,35
31:12,15,25=0
33:12,15,34=35,45
34:12,15,35=45
37:12,23,24=25,35,45
39:12,23,25=34,45
41:12,23,34=35,45
42:12,23,35=45
44:12,24,25=34,35
46:12,24,34=35,45
47:12,24,35=45
49:12,25,34=35,45
50:12,25,35=45
50:12,34,35=0
53:13,14,15=23,24,25
56:13,14,23=25,35,45
59:13,14,24=25,35,45
61:13,14,25=35,45
61:13,14,34=0
61:13,14,35=0
64:13,15,23=24,34,45
67:13,15,24=25,34,45
69:13,15,25=34,45
69:13,15,34=0
69:13,15,35=0
72:13,23,24=25,35,45
74:13,23,25=34,45
76:13,23,34=35,45
77:13,23,35=45
79:13,24,25=34,35
81:13,24,34=35,45
82:13,24,35=45
84:13,25,34=35,45
85:13,25,35=45
85:13,34,35=0
89:14,15,23=24,25,34,35
91:14,15,24=34,35,
93:14,15,25=34,35
93:14,15,34=0
93:14,15,35=0
96:14,23,24=25,35,45
98:14,23,25=34,45
100:14,23,34=35,45
101:14,23,35=45
103:14,24,25=34,35
105:14,24,34=35,45
106:14,24,35=45
108:14,25,34=35,45
109:14,25,35=45
109:14,34,35=0
112:15,23,24=25,35,45
114:15,23,25=34,45
116:15,23,34=35,45
117:15,23,35=45
119:15,24,25=34,35
121:15,24,34=35,45
122:15,24,35=45
124:15,25,34=35,45
125:15,25,35=45
125:15,34,35=0
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