/in/foo.cc: In function 'int main()':
/in/foo.cc:17:9: warning: unused variable 'abminx' [-Wunused-variable]
  double abminx=(ax+bx)/2,
         ^~~~~~
/in/foo.cc:18:4: warning: unused variable 'abminy' [-Wunused-variable]
    abminy=(ay+by)/2,
    ^~~~~~
/in/foo.cc:20:9: warning: unused variable 'kab' [-Wunused-variable]
  double kab,kabmin;
         ^~~
/in/foo.cc:20:13: warning: unused variable 'kabmin' [-Wunused-variable]
  double kab,kabmin;
             ^~~~~~