how to reshape 2D to 3D in loop, when submatrix has different size

% example matrix
A =[1,1,2
    1,5,2];

B =[2,2,4
    2,4,7];

C =[3,2,4
    3,4,7];

D =[4,2,4
    4,2,4
    4,4,7];

Input=[A;B;C;D];

%Extract the submatrix and defined as X(i).This based on their common ID=i [m,d]=size(Input);

ID.uni=unique(Input(:,1));       % unique all the ID: 01,02...k
k=length(ID.uni);
X=[];
for i=1:k
    rows_i= find(Input(:,1)==ID.uni(i));  % index which rows have the same ID
    X(:,:,i)=Input([rows_i],:);
end