[petsc-users] use mpic++ instead of mpicc

[Degang Wu]

Hi,

I am new to Petsc and Slepc, and I rely on the makefile provided in the 
example code folders to compile. For example, the makefile in 
src/eps/examples/tutorials/makefile. How should I modify the makefile so 
that make will use mpic++ rather than mpicc to compile and link?

Wu Degang