function CFL=transp2d(N,M)
% L is the number of discretization points in each direction (1,2)
% M is the number of time steps
tau=0.5/M;
CFL=tau*(N+1)
I = speye(N,N);
E = sparse(2:N,1:N-1,???,N,N);
A = kron(I,I-???)*(N+1);
mat=speye(N*N,N*N)-tau*???;
u=ones([N*N,1]);
for i=1:M;
  u=mat*???;
end
%plot sol
x=linspace(1/L,1-1/L,L);
y=linspace(1/L,1-1/L,L);
[xx, yy] = meshgrid (x, y);
k=0;
for i=1:L
 for j=1:L
  k=k+1;
  sol(i,j)=u(k);
  sol(i,j)=u(k);
 end
end
mesh(x,y,sol);
end