The wronskian solution of the constrained discrete KP hierarchy

From the constrained discrete KP (cdKP) hierarchy, the Ablowitz-Ladik lattice has been derived. By means of the gauge transformation, the Wronskian solution of the Ablowitz-Ladik lattice have been given. The $u_1$ of the cdKP hierarchy is a Y-type soliton solution for odd times of the gauge transformation, but it becomes a dark-bright soliton solution for even times of the gauge transformation. The role of the discrete variable $n$ in the profile of the $u_1$ is discussed.