Method inverse

crates/vm/src/builtins/int.rs:416–423

(a: BigInt, n: &BigInt)

                        if a.is_negative() { a + n } else { a }
                    }
                    fn inverse(a: BigInt, n: &BigInt) -> Option<BigInt> {
                        let ExtendedGcd { gcd, x: c, .. } = a.extended_gcd(n);
                        if gcd.is_one() {
                            Some(normalize(c, n))
                        } else {
                            None
                        }
                    }
                    let a = inverse(a % modulus, modulus).ok_or_else(|| {
                        vm.new_value_error("base is not invertible for the given modulus")
                    })?;