function [A,b]=Gauss_pivot(A,b)

[n,n]=size(A);
for p=1:n
    [t,A(:,p)]=VG(A(:,p),p);
    for j=p+1:n
        A(:,j)=VGY(A(:,j),p,t);
    end
    b=VGY(b,t,p);
end