foo.cc: In function 'int main()':
foo.cc:22:26: warning: 'arr' may be used uninitialized [-Wmaybe-uninitialized]
   22 |         int gongyue = gcd(arr[0], arr[1]);
      |                       ~~~^~~~~~~~~~~~~~~~
foo.cc:16:13: note: 'arr' declared here
   16 |         int arr[10000];
      |             ^~~
foo.cc:22:26: warning: 'arr' may be used uninitialized [-Wmaybe-uninitialized]
   22 |         int gongyue = gcd(arr[0], arr[1]);
      |                       ~~~^~~~~~~~~~~~~~~~
foo.cc:16:13: note: 'arr' declared here
   16 |         int arr[10000];
      |             ^~~

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