how to write this boundary conditions in matlab code

This is my boundary condition i need to use explicit ftcs numerical difference scheme

𝐶|𝑥=0 = 1 mg/L, 𝑑𝐶 𝑑𝑥 |𝑥=𝐿 = 0, 𝐶|𝑡=0 = 1 mg/L

[Torsten]

No need to use a difference scheme.

Solution is C = 1 mg/L for all x and all t.