/in/foo.cc: In function 'int main()':
/in/foo.cc:27:9: warning: unused variable 'sum' [-Wunused-variable]
     int sum=0;
         ^~~
/in/foo.cc:29:12: warning: unused variable 'dd' [-Wunused-variable]
     double dd[100000];
            ^~
/in/foo.cc:30:9: warning: unused variable 'x0' [-Wunused-variable]
     int x0=0,y0=0;
         ^~