XC XB XA IB IA
= 2 lower beds & 2 upper beds / 
= sofa bed / 
= connecting cabins / 
= cabins with porthole(s) / 
= 2 lower beds
XC XB XA IB IA
= 2 lower beds & 2 upper beds / = sofa bed / = connecting cabins / = cabins with porthole(s) / = 2 lower beds