foo.c: In function 'main':
foo.c:16:9: warning: right-hand operand of comma expression has no effect [-Wunused-value]
   16 |  for(a=0,a<n,a++)
      |         ^
foo.c:16:17: error: expected ';' before ')' token
   16 |  for(a=0,a<n,a++)
      |                 ^
      |                 ;
foo.c:16:17: error: expected expression before ')' token
foo.c:17:16: error: 'num' undeclared (first use in this function)
   17 |  {printf("%d ",num[a]);
      |                ^~~
foo.c:17:16: note: each undeclared identifier is reported only once for each function it appears in

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