#Butterfly network with 16 terminal nodes and 32 switches
48 2

 0 T 16
 1 R 16
 2 R 17
 3 R 17
 4 R 18
 5 R 18
 6 R 19
 7 R 19
 8 R 20
 9 R 20
10 R 21
11 R 21
12 R 22
13 R 22
14 R 23
15 R 23
16 N 24 28
17 N 25 29
18 N 26 30
19 N 27 31
20 N 28 24
21 N 29 25
22 N 30 26
23 N 31 27
24 N 32 34
25 N 33 35
26 N 32 34
27 N 33 35
28 N 36 38
29 N 37 39
30 N 36 38
31 N 37 39
32 N 40 41
33 N 40 41
34 N 42 43
35 N 42 43
36 N 44 45
37 N 44 45
38 N 46 47
39 N 46 47
40 N  0  1
41 N  2  3
42 N  4  5
43 N  6  7
44 N  8  9
45 N 10 11
46 N 12 13
47 N 14 15