foo.c: In function 'main':
foo.c:13:21: warning: variable 'a' set but not used [-Wunused-but-set-variable]
   13 |                 int a[x+1];
      |                     ^
foo.c:11:30: warning: 'h' may be used uninitialized [-Wmaybe-uninitialized]
   11 |         int main(){int x;int h,t;
      |                              ^

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