foo.cc: In function 'int gy(int, int)':
foo.cc:5:6: warning: unused variable 'imin' [-Wunused-variable]
  int imin,imax;
      ^~~~
foo.cc:13:9: warning: 'imax' may be used uninitialized in this function [-Wmaybe-uninitialized]
  return imax;
         ^~~~
foo.cc: In function 'int main()':
foo.cc:5:11: warning: 'imax' may be used uninitialized in this function [-Wmaybe-uninitialized]
  int imin,imax;
           ^~~~

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