View Compilation Error

0_0_36233001_27854.cpp: In function 'int getCircleCircleIntersection(Circle, Circle, Point&, Point&)':
0_0_36233001_27854.cpp:53:33: error: 'Dist' was not declared in this scope
   double d = sqrt(Dist(C1.c,C2.c));
                                 ^