2

program Project1;
Type
    point = record
      id:integer;
      x,y:integer;
    end;
var
  mass:array[1..64] of point;
  i,g,kol:integer;
  xs,ys,vs:integer;
  s:extended;
  ID,vis:integer;

begin
  s:=0;
  for i:=1 to 64 do
      readln(mass[i].id,mass[i].x,mass[i].y);
  readln(kol);
  xs:=mass[1].x; ys:=mass[1].y; vs:=0;
  for i:=1 to kol do begin
     readln(ID,vis);
     for g:=1 to 64 do
         if (mass[g].id=ID) then break;
     s:=s+((sqrt(sqr(mass[g].x-xs)+sqr(mass[g].y-ys)+sqr(vis-vs))*0.4)/3);
     xs:=mass[g].x;ys:=mass[g].y;vs:=vis;
  end;
  s:=s+((sqrt(sqr(mass[1].x-xs)+sqr(mass[1].y-ys)+sqr(0-vs))*0.4)/3);
  writeln(s:5:5);
  readln;
end.