View Compilation Error

0_0_16826645_23757.cpp: In function 'double Min(Node, Node)':
0_0_16826645_23757.cpp:21:67: error: 'sqrt' was not declared in this scope
  return sqrt((a.y - b.y) * (a.y - b.y) + (a.x - b.x) * (a.x - b.x));
                                                                   ^
0_0_16826645_23757.cpp: In function 'void Prim(int)':
0_0_16826645_23757.cpp:36:32: error: 'memset' was not declared in this scope
  memset(Flag,false,sizeof(Flag));
                                ^