malachite_base/unsigned_vector/arithmetic/
mod_element_product.rs

1// Copyright © 2026 Mikhail Hogrefe
2//
3// This file is part of Malachite.
4//
5// Malachite is free software: you can redistribute it and/or modify it under the terms of the GNU
6// Lesser General Public License (LGPL) as published by the Free Software Foundation; either version
7// 3 of the License, or (at your option) any later version. See <https://www.gnu.org/licenses/>.
8
9use crate::num::arithmetic::traits::ModElementProduct;
10use crate::num::basic::unsigneds::PrimitiveUnsigned;
11use crate::unsigned_vector::UnsignedVector;
12
13impl<T: PrimitiveUnsigned> ModElementProduct<T> for UnsignedVector<T> {
14    type Output = T;
15
16    /// Returns the product of the elements of an [`UnsignedVector`] modulo another number $m$,
17    /// taking the vector by reference. The elements must already be reduced.
18    ///
19    /// The 0-dimensional vector has no elements, and their product is 1, reduced: 0 when $m = 1$.
20    ///
21    /// $$
22    /// f(v, m) = \prod_i v_i \bmod m.
23    /// $$
24    ///
25    /// # Worst-case complexity
26    /// $T(n) = O(n)$
27    ///
28    /// $M(n) = O(1)$
29    ///
30    /// where $T$ is time, $M$ is additional memory, and $n$ is `self.dimension()`.
31    ///
32    /// # Panics
33    /// Panics if `m` is zero, or if any element is greater than or equal to `m`. As soon as the
34    /// partial product is zero, the remaining elements are not examined, so an unreduced element
35    /// after that point is not detected.
36    ///
37    /// # Examples
38    /// ```
39    /// use core::str::FromStr;
40    /// use malachite_base::num::arithmetic::traits::ModElementProduct;
41    /// use malachite_base::unsigned_vector::UnsignedVector;
42    ///
43    /// let v = UnsignedVector::<u8>::from_str("(3, 5, 7)").unwrap();
44    /// assert_eq!(v.to_mod_element_product(10), 5);
45    /// let v = UnsignedVector::<u8>::from_str("()").unwrap();
46    /// assert_eq!(v.to_mod_element_product(10), 1);
47    /// ```
48    #[inline]
49    fn to_mod_element_product(&self, m: T) -> T {
50        T::mod_product(self.elements.iter(), m)
51    }
52
53    /// Returns the product of the elements of an [`UnsignedVector`] modulo another number $m$,
54    /// taking the vector by value. The elements must already be reduced.
55    ///
56    /// The 0-dimensional vector has no elements, and their product is 1, reduced: 0 when $m = 1$.
57    ///
58    /// $$
59    /// f(v, m) = \prod_i v_i \bmod m.
60    /// $$
61    ///
62    /// # Worst-case complexity
63    /// $T(n) = O(n)$
64    ///
65    /// $M(n) = O(1)$
66    ///
67    /// where $T$ is time, $M$ is additional memory, and $n$ is `self.dimension()`.
68    ///
69    /// # Panics
70    /// Panics if `m` is zero, or if any element is greater than or equal to `m`. As soon as the
71    /// partial product is zero, the remaining elements are not examined, so an unreduced element
72    /// after that point is not detected.
73    ///
74    /// # Examples
75    /// ```
76    /// use core::str::FromStr;
77    /// use malachite_base::num::arithmetic::traits::ModElementProduct;
78    /// use malachite_base::unsigned_vector::UnsignedVector;
79    ///
80    /// let v = UnsignedVector::<u8>::from_str("(3, 5, 7)").unwrap();
81    /// assert_eq!(v.into_mod_element_product(10), 5);
82    /// let v = UnsignedVector::<u8>::from_str("()").unwrap();
83    /// assert_eq!(v.into_mod_element_product(10), 1);
84    /// ```
85    #[inline]
86    fn into_mod_element_product(self, m: T) -> T {
87        T::mod_product(self.elements.into_iter(), m)
88    }
89}
malachite_base/unsigned_vector/arithmetic/mod_element_product.rs

malachite_base/unsigned_vector/arithmetic/
mod_element_product.rs
