MATLAB: To change 12×12 matrix to 6X12

Question

How can i add a loop to add the 1st two rows of a matrix and then 3rd and 4th row of a matrix and so on till the addition of 11th and 12th row so as to get a 6×12 matrix instead of 12×12 matrix.

for example:

r= 1 2 3 4

5 6 7 8

9 0 1 2

3 4 5 6]

that is 4×4 matrix.

answer= 6 8 10 12

12 4 6 8

converted to 2×4 matrix.

so similar manner how to convert 12×12 matrix to 6×12 matrix using any loop or normal command.

Answer 1

Answer = reshape(r(1:2:end)+r(2:2:end),[],size(r,2))