Riemann Zeta Function C++ Program

[codyysb]

Create a program to compute the Riemann zeta function for real values of x > 1. There will be two while loops in the program. The outer loop will allow the user to continue entering in numbers for x as long as he or she types in ‘y’ to the question “Do you want to continue? Type ‘y’ for yes, anything else for no.” The inner loop will continue adding terms to the sum for the zeta function as long as the terms remain greater than 10^-7 (1e–7).

I have an idea of creating the program, but what would be the most efficient way?