  We present a general solution of relativistic (1+1)-dimensional hydrodynamics
for a perfect fluid flowing along the longitudinal direction as a function of
time, uniformly in transverse space. The Khalatnikov potential is expressed as
a linear combination of two generating functions with polynomial coefficients
of 2 variables. The polynomials, whose algebraic equations are solved, define
an infinite-dimensional basis of solutions. The kinematics of the
(1+1)-dimensional flow are reconstructed from the potential.
