function [L,U]= lugauss(A)
%lugauss(fattorizazzione LU senza pivoting): [L,U]= lugauss(A)
n=size(A,1); 
U=A;
L=diag(diag(ones(n)));
for k=1:n-1 
  L(k+1:n,k)=U(k+1:n,k)/U(k,k); 
  for s=k+1:n 
      for j=k:n 
          U(s,j)=U(s,j)-L(s,k)*U(k,j) ; 
    end
  end
end
