1.
If z1=z2==zn=1|z_1| = |z_2| = \ldots = |z_n| = 1, then the value of z1+z2++zn1z1+1z2++1zn|z_1 + z_2 + \ldots + z_n| - \left|\frac{1}{z_1} + \frac{1}{z_2} + \ldots + \frac{1}{z_n}\right| is