Function mod_add_const 

pub fn mod_add_const(
    b: &[usize],
    overflow: usize,
    a_const: usize,
    n_const: usize,
) -> U

A quantum circuit that adds constants and multiplies modular operations using constants, and stores the result in one input bit.

|b⟩|overflow:0⟩ → |a+b mod N⟩|0⟩

• overflow = |0⟩.
• a, N: const.
• N < 2^(n+1).
• a, b < N.
• b.len() == n.

Required number of qubits: n(b) + 1(overflow) = n + 1