  Jets, jet-medium interaction and hydrodynamic evolution of fluctuations in
initial parton density all lead to the final anisotropic dihadron azimuthal
correlations in high-energy heavy-ion collisions. We remove the harmonic flow
background and study the net correlations from different sources with different
initial conditions within the AMPT model. We also study $\gamma$-hadron
correlations which are only influenced by jet-medium interactions.
