foo.cc: In function 'int main()':
foo.cc:36:6: warning: unused variable 'n' [-Wunused-variable]
   36 |  int n, a[100], x;
      |      ^
foo.cc:36:9: warning: unused variable 'a' [-Wunused-variable]
   36 |  int n, a[100], x;
      |         ^
foo.cc:36:17: warning: unused variable 'x' [-Wunused-variable]
   36 |  int n, a[100], x;
      |                 ^

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