integer :: a,b
logical :: flag = .false.

read*,a,b

if( mod(a,3)==0 ) flag = .true.
if( mod(b,3)==0 ) flag = .true.
if( mod(a+b,3)==0 ) flag = .true.

if(flag)then
  print*,'Possible'
else
  print*,'Impossible'
end if
end