yoshi@erdos:~/Main/www/2004i/mac328/exx/sec18.4$ gcc prog18.2.c prog18.3.driver_ft.c prog17.10.c
yoshi@erdos:~/Main/www/2004i/mac328/exx/sec18.4$ a.out 8 10 < fig18.9.gr 
8 vertices, 10 edges
 0:  7  5  2
 1:  7
 2:  6  0
 3:  5  4
 4:  5  7  3  6
 5:  0  4  3
 6:  4  2
 7:  0  1  4
pre[]: 0 2 7 5 3 4 6 1 
 st[]: 0 7 6 5 7 4 4 0 
0-0 tree
  0-7 tree
    7-0 parent
    7-1 tree
      1-7 parent
    7-4 tree
      4-5 tree
        5-0 back
        5-4 parent
        5-3 tree
          3-5 parent
          3-4 back
      4-7 parent
      4-3 down
      4-6 tree
        6-4 parent
        6-2 tree
          2-6 parent
          2-0 back
  0-5 down
  0-2 down
yoshi@erdos:~/Main/www/2004i/mac328/exx/sec18.4$