How to complete Gaussian elimination?

Hello everyone, I am looking for an answer using Gaussian elimination, and the values ​​diverge at the end. How do I fix it to get an accurate answer?

Here is my code.

clc; clear all; close all;

A = [2 0 1 ; -2 4 1 ;-1 -1 3];

b = [8 0 2]';

sz = size(A,1);

disp ([A b]);

for i = 2 :1: sz

for j = 1:1:i-1

k = A(j,j)/A(i,j);

A(i,:) = k * A(i,:) - A(j,:);

b(i) = k * b(i) - b(j);

disp([A b]);

pause(3)

end

end

for i = sz-1:-1:1

for j = sz:-1:i+1

k = A(j,j)/A(i,j);

A(i,:) = k*A(i,:)-A(j,:);

b(i) = k* b(i) - b(j);

disp([A b]);

pause(3)

end

end

x = b./diag(A);

disp(x);

Answer 1

[Sulaymon Eshkabilov]

Here is the corrected code:

A = [2 0 1; -2 4 1; -1 -1 3];
b = [8 0 2]';
sz = size(A, 1);
disp([A b]);

     2     0     1     8
    -2     4     1     0
    -1    -1     3     2

% Forward elimination
for i = 1:sz-1
    for j = i+1:sz
        k = A(j, i) / A(i, i);
        A(j, :) = A(j, :) - k * A(i, :);
        b(j) = b(j) - k * b(i);
        disp([A b]);
        pause(3);
    end
end

     2     0     1     8
     0     4     2     8
    -1    -1     3     2

    2.0000         0    1.0000    8.0000
         0    4.0000    2.0000    8.0000
         0   -1.0000    3.5000    6.0000

     2     0     1     8
     0     4     2     8
     0     0     4     8

% Back Substitution:
x = zeros(sz, 1);
for i = sz:-1:1
    x(i) = (b(i) - A(i, i+1:end) * x(i+1:end)) / A(i, i);
end

disp('FINAL Solution:  ');

FINAL Solution:  

disp(x);

     3
     1
     2