MATLAB: I want to insert rows to matrix with condition

Question

i have this matrix

D=[ 1 2 3 4 0 0

    1 2 5 3 4 0
    1 3 1 0 0 0
    1 3 4 2 0 0
    2 1 6 0 0 0
    2 1 5 4 0 0
    2 3 4 2 0 0
    2 3 5 4 1 0
    3 1 2 0 0 0
    3 1 4 0 0 0 ]

i want to insert at each same raw ( same the 1&2 columns) for example

1 2 3 4 0 0

1 2 5 3 4 0

another raw (like 1&2 columns and 0 0 0 0)

1 2 0 0 0 0

for the matrix D become

D=[1 2 0 0 0 0

    1 2 3 4 0 0
    1 2 5 3 4 0
    1 3 0 0 0 0
    1 3 1 0 0 0
    1 3 4 2 0 0
    2 1 0 0 0 0
    2 1 6 0 0 0
    2 1 5 4 0 0
    2 3 0 0 0 0
    2 3 4 2 0 0
    2 3 5 4 1 0
    3 1 0 0 0 0
    3 1 2 0 0 0
    3 1 4 0 0 0 ]

Answer 1

 your_mat = sortrows([a;b]);