N = 1;

A = -2*eye(N); % N tells how many rows and columns in the matrix
L = 5;
K = 1;
% R = K/delta_X^2       (1)
%L = N*delta_x          (2)
% => delta_x = L / N    (3)
% (2) + (3) => R = K/((L/N)*(L/N))
R = K/((L/N)*(L/N));
L1 = [1:N-1]*0;  % 1xN-1 = [0 0 0 0 ... ] n-1 klp
L2 = [1:N]'*0;
R1 = [L2 [eye(N-1); L1]];
R2 = R1';
A(N,N) = -1;
A = R*(A+R1+R2);

% B matrix
B = L2;
B(1) = R; %B = [R 0 0 0...0]
C = L2' % L2 Transpose