Yinyu:

The graphs I have in my homepage are rather small (only up to 500 nodes).
But I once obtained the following graph generator, called "rudy", of which 
I will send you the c files in the following two mails. They are:

gb_lib.c        basic graph algorithms of Knuth
rudy.c          generator based on that due to Giovanni Rinaldi

Compiling: gcc gb_lib.c rudy.c -lm -o rudy

Good luck and best wishes,

  Stefan

PS: Please note my new address.

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 Stefan E. Karisch                  
 Department of Mathematical Modelling     Phone:      +45 45 25 33 85
 Technical University of Denmark          Fax:        +45 45 88 26 73 
 DTU-Building 321                         E-mail:     sk@imm.dtu.dk
 DK-2800 Lyngby, Denmark                  http://www.diku.dk/~karisch
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