Evaluating <1s|1s>

Hi all,

I need to numerically evaluate integrals of the form <1s|1s>, <1s|z|1s>, and then <1s|z|npz> with n from 2 to 6. How do I do this? It needs to be done in a C++ program that I have written. I have all of the wavefunctions in the program, they are evaluated properly.

Can anyone help?

Thanks in advance