/in/foo.cc: In function 'int main()':
/in/foo.cc:23:39: warning: format '%lf' expects argument of type 'double*', but argument 2 has type 'int*' [-Wformat=]
         scanf("%lf%lf",&xxx[i],&yyy[i]);
                                       ^
/in/foo.cc:23:39: warning: format '%lf' expects argument of type 'double*', but argument 3 has type 'int*' [-Wformat=]