How can I use index numbers as markers to plot in MATLAB

x=[1 1 2 2 3 3 4 4];
y=[2 3 1 2 3 4 3 2];
figure(1)
scatter(x,y)
figure(2)
axis([min(x)-1, max(x)+1, min(y)-1, max(y)+1])
for k=1:length(x)
    text(x(k),y(k),num2str(k))
end

See original link here.