/in/foo.cc: In function 'int main()':
/in/foo.cc:53:9: warning: unused variable 'cR' [-Wunused-variable]
     int cR,cC,lR,lC;
         ^~
/in/foo.cc:53:12: warning: unused variable 'cC' [-Wunused-variable]
     int cR,cC,lR,lC;
            ^~
/in/foo.cc:53:15: warning: unused variable 'lR' [-Wunused-variable]
     int cR,cC,lR,lC;
               ^~
/in/foo.cc:53:18: warning: unused variable 'lC' [-Wunused-variable]
     int cR,cC,lR,lC;
                  ^~