Function algos::search::exponential

pub fn exponential<T: Ord>(a: &[T], x: &T) -> Result<usize, usize>

Exponential Search: Search for the value 'x' in an array.

Returns Err holding the leftmost term if 'x' not found.

Obs.: Variation of binary search.

Case	Time complexity	Space complexity
Best:	Ω(1)
Avrg:	θ(log(n))
Worst:	O(log(n))	O(1)

Example

use algos::search;

let v = [1, 3, 4, 8, 11, 17, 23];

let find = search::exponential(&v, &11);
assert_eq!(find, Ok(4));

let find2 = search::exponential(&v, &19);
assert_eq!(find2, Err(6));