$ cflow animal.c 
1       main: int(), <animal.c 15> 
2               printf: <> 
3               yes: int(), <animal.c 55> 
4               gensis: int(), <animal.c 28> 
5                       make_node: struct*(), <animal.c 46> 
6                               malloc: <> 
7                               strcpy: <> 
8               endgame: int(), <animal.c 63> 
9                       printf: 2 
10                      yes: 3 
11                      gets: <> 
12                      make_node: 5 
13              guess: int(), <animal.c 33> 
14                      printf: 2 
15                      yes: 3 
16                      endgame: 8 
17                      guess: 13 
 
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