/in/foo.cc: In function 'int main()':
/in/foo.cc:50:37: warning: use of assignment suppression and length modifier together in gnu_scanf format [-Wformat=]
   scanf("%lf%lf%*lf",&a[i].x,&a[i].y);
                                     ^
/in/foo.cc:52:37: warning: use of assignment suppression and length modifier together in gnu_scanf format [-Wformat=]
   scanf("%lf%lf%*lf",&b[i].x,&b[i].y);
                                     ^
/in/foo.cc:61:33: warning: suggest parentheses around arithmetic in operand of '^' [-Wparentheses]
     if( fabs(cross)<EPS && (a[i]-b[k]^a[j]-b[k])>EPS )
                             ~~~~^~~~~