allocation random matrices in a big matrix

hi, so if i have a matrix M= (N,L) =(20,30) and i want to allocate some cells of this matrix

exemple: V1 = 1 1 1: means V1 will take a place in the matrix M starting at L=1

1 0 0

V2= 1 1 1 1 : same for this matrix , V2 take place in the matrix M starting at L=1

1 0 0 0 means the first column of V2 will be in the first

1 0 0 0 column of M

then V3 = 1 1 1 will be allocated starting from L=2

1 1 0

Thank you