test3(~B)
B 1
ctor 1
set 1
disp 1
dtor 1
B(5)
Set(0,0)
disp() 0 0 0 0 0 
~B()
B(6)
Set(1,0.1)
disp() 1 1.1 1.2 1.3 1.4 1.5 
~B()
B(7)
Set(2,0.2)
disp() 2 2.2 2.4 2.6 2.8 3 3.2 
~B()