  Large-scale calculation based on the multi-configuration Skyrme density
functional theory is performed for the light N=Z even-even nucleus, 12C.
Stochastic procedures and the imaginary-time evolution are utilized to prepare
many Slater determinants. Each state is projected on eigenstates of parity and
angular momentum. Then, performing the configuration mixing calculation with
the Skyrme Hamiltonian, we obtain low-lying energy-eigenstates and their
explicit wave functions. The generated wave functions are completely free from
any assumption and symmetry restriction. Excitation spectra and transition
probabilities are well reproduced, not only for the ground-state band, but for
negative-parity excited states and the Hoyle state.
