function power5(A,Y,e,N)
k=1;
u=1;
%LU分解
[L,U]=Crout(A);
for i=1:N
    Z=Y/L;
    X=Z/U;
    Xr=max(X);
    t=Xr;
    Y=X/t;
    if abs(1/t-1/u)<e
        T=1/t
        Y
        break;
    end
    if k<N
        k=k+1;
        u=t;
    end
end