Function rudac::algo::search::exponential_search_with

pub fn exponential_search_with<T, F>(
    slice: &[T], 
    item: &T, 
    compare: &F
) -> Option<usize> where
    F: Fn(&T, &T) -> Ordering, 

Exponential search is a search algorithm that finds the position of a target value within a sorted array. Suitable for searching sorted, unbounded/infinite lists. Returns index of the found item, None otherwise

Arguments

• slice: slice of ordered data
• item: item to be searched for
• compare: custom comparison closure

Examples

use rudac::algo::search::exponential_search_with;

// consider a vector of 2d points
let mut vec = vec![(3,1), (4,2), (5,3), (3,4), (10,5), (2,6), (6,7), (9,8), (8,9), (1,10)];
 
let compare = |x1: &(usize, usize),x2: &(usize, usize)| {x1.1.cmp(&x2.1)};
assert_eq!(vec[exponential_search_with(&vec, &(3,1), &compare).unwrap()], (3,1));
assert_eq!(vec[exponential_search_with(&vec, &(4,2), &compare).unwrap()], (4,2));
assert_eq!(vec[exponential_search_with(&vec, &(5,3), &compare).unwrap()], (5,3));

assert_eq!(exponential_search_with(&vec, &(1,11), &compare), None);
assert_eq!(exponential_search_with(&vec, &(1,12), &compare), None);
assert_eq!(exponential_search_with(&vec, &(1,13), &compare), None);