Function malachite_base::iterators::comparison::is_weakly_descending

pub fn is_weakly_descending<I: Iterator>(xs: I) -> bool where
    I::Item: Ord, 

Determines whether each element of an iterator is less than or equal to the preceding one.

This function will hang if given an infinite weakly descending iterator.

$$ f((x_k)_{k=0}^N) = \bigwedge_{k=1}^N{x_k \leq x_{k-1}}, $$ where $N$ may be $\infty$.

Examples

use malachite_base::iterators::comparison::is_weakly_descending;

assert_eq!(is_weakly_descending([4, 3, 2, 1].into_iter()), true);
assert_eq!(is_weakly_descending([4, 2, 2, 1].into_iter()), true);
assert_eq!(is_weakly_descending([4, 2, 3, 1].into_iter()), false);