Struct Iter

pub struct Iter<T: BorrowMut<[usize]>> { /* private fields */ }

Iterates over all k-combinations.

The k-combinations are iterated in value order:

let mut iter = Iter::new(k);
for i in 0 .. combination(n, k) {
    assert_eq!(encode(iter.get()), i);
    iter.advance();
}

Examples

To iterate over all k-combinations in a set of n elements:

let mut iter = Iter::new(k);
for _ in 0 .. combination(n, k) {
    process(iter.get());
    iter.advance();
}

In a no-std environment, you can pass a buffer of size K:

let mut buffer = [0usize; K];
let mut iter = Iter::new_with_buffer(&mut buffer[..]);

Implementations

impl Iter<Vec<usize>>

pub fn new(k: usize) -> Iter<Vec<usize>>

Constructs an iterator.

impl<T: BorrowMut<[usize]>> Iter<T>

pub fn new_with_buffer(buffer: T) -> Iter<T>

Constructs an iterator with a buffer.

pub fn new_from(xs: T) -> Iter<T>

Constructs an iterator starting from a given k-combination.

Panics

Panics in debug mode if xs is not increasing.

pub fn get(&self) -> &[usize]

Returns the current combination.

pub fn advance(&mut self)

Advances to the next combination.