foo.c: In function 'main':
foo.c:8:13: warning: variable 'a' set but not used [-Wunused-but-set-variable]
    8 |         int a[x+1];
      |             ^
foo.c: In function 'en':
foo.c:18:18: error: 'a' undeclared (first use in this function)
   18 | for(h=0;h<sizeof a[]/sizeof a[0];h++){
      |                  ^
foo.c:18:18: note: each undeclared identifier is reported only once for each function it appears in
foo.c:18:20: error: expected expression before ']' token
   18 | for(h=0;h<sizeof a[]/sizeof a[0];h++){
      |                    ^
foo.c:19:25: error: expected ')' before ';' token
   19 |         printf("%d",a[h];)
      |               ~         ^
      |                         )
foo.c:19:27: error: expected ';' before '}' token
   19 |         printf("%d",a[h];)
      |                           ^
      |                           ;
   20 | }
      | ~                          

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