malachite-base 0.14.0

A collection of utilities, including new arithmetic traits and iterators that generate all values of a type.
Documentation 
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// Copyright © 2026 Mikhail Hogrefe
//
// This file is part of Malachite.
//
// Malachite is free software: you can redistribute it and/or modify it under the terms of the GNU
// Lesser General Public License (LGPL) as published by the Free Software Foundation; either version
// 3 of the License, or (at your option) any later version. See <https://www.gnu.org/licenses/>.

use core::str::FromStr;
use malachite_base::test_util::generators::unsigned_vector_gen;
use malachite_base::unsigned_vector::UnsignedVector;
use malachite_base::vector::Vector;
#[test]
fn test_pivot() {
    let test = |s, out: Option<&str>| {
        let v = UnsignedVector::<u64>::from_str(s).unwrap();
        assert_eq!(v.pivot().map(|x| x.to_string()).as_deref(), out);
        assert_eq!(v.pivot_index().is_some(), out.is_some());
    };
    test("()", None);
    test("(0)", None);
    test("(0, 0, 0)", None);
    test("(5)", Some("5"));
    test("(0, 0, 3, 0, 5)", Some("3"));
    test("(7, 0, 0)", Some("7"));
    test("(0, 18446744073709551615)", Some("18446744073709551615"));
}

#[test]
fn pivot_properties() {
    unsigned_vector_gen().test_properties(|v| {
        let pivot = v.pivot();
        // There is a pivot exactly when some element is nonzero.
        assert_eq!(pivot.is_none(), v.elements.iter().all(|x| *x == 0));
        // It is the first nonzero element: every element before it is zero, and its index is
        // `pivot_index`.
        let index = v.pivot_index();
        assert_eq!(index.is_some(), pivot.is_some());
        if let Some(i) = index {
            let i = usize::try_from(i).unwrap();
            assert_eq!(pivot, Some(v[i]));
            assert!(v.elements[..i].iter().all(|x| *x == 0));
        }
        if let Some(i) = v.elements.iter().position(|x| *x != 0) {
            assert_eq!(pivot, Some(v.elements[i]));
        }
    });
}