program
	implicit none
	integer,parameter::n=3,kamx=15
	real,dimension(1:n,1:n)::A(n,n)
	real,dimension(1:n)::x(n),y(n),xip(n)
	integer::j,k
	open(UNIT=80,FILE='resultat.dat',status='unknown')

	       !matrice A(n,n)
        A(1,:)=(/4.,1.,0./)
	  A(2,:)=(/8.,2.,0./)
	  A(3,:)=(/7.,9.,3./)

	       !vecteur initial
	  x(:)=(/0.,1.,0./)

	       !methode de la puissance itérée
	   y(:)=x(:)
         k=1
		do j=1:n

       while(k<=15)then
	        x(j)=A(j,j)*y(k-1)
	      	xip(j(k))=max(A(j,j),x(:))
	         y(j)=x(j)/xip(j(k))

	   end

	print*,'       k',  '      lamda',  '       vecteur propre'
	write(*,*)

	do k=1,kmax
	  write(*,25)k,x(k),y(k),y(k+1),y(k+2)
 25      format(3X,I5,1X,1PE10.2,5X,3(1PE10.2))
   	      enddo


	write(80,*)'      k','     lamda','      vecteur propre	'
	write(80,*)

	do k=1,kmax
	 write(80,29)k,x(k),y(k),y(k+1),y(k+2)
29	   format(3X,I5,1X,1PE10.3,5X,3(1PE10.3))
	   	  enddo


	  end program