function [L,U] = lu_right (A)
n = size (A,1)
L = eye (n) ;
U = zeros (n) ;
for k = 1:n
    U (k,k:n) = A (k,k:n) ;				       % (7.4) and (7.5)
    L (k+1:n,k) = A (k+1:n,k) / U (k,k) ;				 % (7.6)
    A (k+1:n,k+1:n) = A (k+1:n,k+1:n) - L (k+1:n,k) * U (k,k+1:n) ;	 % (7.7)
end
