foo.c: In function 'main':
foo.c:5:13: error: 'a' undeclared (first use in this function)
  int maxNum=a[0], maxCount=1;
             ^
foo.c:5:13: note: each undeclared identifier is reported only once for each function it appears in
foo.c:6:17: error: 'n' undeclared (first use in this function)
  for (int i=1;i<n;i++)
                 ^

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