3D Heat advection C code

Type - 3D
Grid - Structured Cartesian
Case - Heat advection
Method - Finite Volume Method
Approach - Flux based
Accuracy - First order
Scheme - Explicit, QUICK
Temporal - Unsteady
Parallelized - No
Inputs:
[
Length of domain (LX,LY,LZ)
Time step - DT
Material properties - Conductivity (k or kk)
Density - (rho)
Heat capacity - (cp)
Boundary condition and Initial condition.
]
Setup :
The left, top and inside plane boundary is at 100 C and the right, bottom and outside plane boundary is at 0 C. The flow is along the main diagonal.