Crate bound_stl

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Bound-STL

Bound-STL attempts to implement Rust copy of lower_bound and upper_bound manners in C++ STL.

This implementation is adding two traits LowerBound and UpperBound to the follow structures:

  • [..]
  • Vec
  • VecDeque
  • BinaryHeap
  • BTreeset
  • BTreeMap

This repo hosts at bound-stl

Version Documentation License

Usage

use bound_stl::LowerBound;

let v = vec![1, 2, 3, 4, 5];
assert_eq!(v.lower_bound(&3), Ok(2));
assert_eq!(v.lower_bound(&6), Err(5));


use bound_stl::UpperBound;

let v = vec![1, 2, 3, 4, 5];
assert_eq!(v.upper_bound(&3), Ok(3));
assert_eq!(v.upper_bound(&6), Err(5));

Traits

  • LowerBound
    find first index where arr[idx] >= v; assume arr is sorted. it is a encapsulation of position method, like position(|e| e.cmp(x) != Ordering::Less), but it returns Err when all elements are less than x.
  • UpperBound
    find first index where arr[idx] > v; assume arr is sorted. it is a encapsulation of position method, like position(|e| e.cmp(x) == Ordering::Greater), but it returns Err when all elements are less than or equal to x.