function R = make_scross(n)

f = 0.7;

M = zeros( n, n);

M(1:ceil(n/3),1:ceil(2*n/3))=ones(ceil(n/3), ceil(2*n/3))*f;
M(1:ceil(2*n/3),1:ceil(n/3))=ones(ceil(2*n/3), ceil(n/3))*f;

M = [ rot90(rot90(M)) rot90(M);rot90(rot90(rot90(M)))  M];

R = reshape(M,1,4*n*n);
