Time delay and time advance of a sequence in MATLAB

%Code for right shift:

n1=input('Enter the required amount of shift');

n=-3:3;

x=[-2 0 1 -3 2 -1 3];

subplot(2,1,1);

stem(n,x);

xlabel('Time sample');

ylabel('Amplitude');

title('Original Signal');

m=n+n1;

subplot(2,1,2);

stem(m,x);

xlabel('Time sample');

ylabel('Amplitude');

title('Advanced signal')

%Code for left shift:

n1=input('Enter the required amount of shift');

n=-3:3;

x=[-2 0 1 -3 2 -1 3];

subplot(2,1,1);

stem(n,x);

xlabel('Time sample');

ylabel('Amplitude');

title('Original Signal');

m=n-n1;

subplot(2,1,2);

stem(m,x);

xlabel('Time sample');

ylabel('Amplitude');

title('Advanced signal');